Astronomija

Kaj se zgodi s krčenjem vesolja ob prisotnosti pritiska Hawkingovega sevanja?

Kaj se zgodi s krčenjem vesolja ob prisotnosti pritiska Hawkingovega sevanja?


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Črne luknje sproščajo Hawkingovo sevanje. Zdaj pa predpostavimo, da se vesolje navsezadnje spet zruši nazaj in pripelje vso snov v eno črno luknjo. Predvidevam, da bi to upognilo tudi ves prostor-čas vesolja in ga ovilo okoli črne luknje.

Kaj se zdaj zgodi s krčenjem vesolja ob pritisku Hawkingovega sevanja?

Bi lahko obstajala stabilna točka, kjer bi se uravnotežili tlak in gravitacija?


V krčečem se, približno 3-sferičnem vesolju s samo črno luknjo, mora Hawkingovo sevanje slediti geodetski črti in se vrniti v črno luknjo, ne da bi pri tem presegalo sevalni pritisk na vesolje kot celoto.

Zato je težko razumeti, kako naj Hawkingovo sevanje vzpostavi ravnovesje z gravitacijo.

Zdi se bolj izvedljivo, da krčenje vesolja lahko v določenem trenutku prepreči nadaljnje izhlapevanje črne luknje, saj se izhlapeli delci in sevanje zaradi celotne ukrivljenosti vesolja-časa usmerjajo nazaj v črno luknjo.


Tudi sam sem se pogosto spraševal o tem, saj se zdi, da to ni zajeto v nobeni literaturi, napisani za laike. Tukaj sem ugotovil iz lastnih razmišljanj

Za oblikovanje navideznih delnih parov (VPP) mora imeti eden negativno energijo, drugi pa pozitivno, da se energija lahko ohrani, kajne? Od tam naredim poskok, ker so te paertike navidezne, razlika med katero je redna (pozitivna) energija in negativna (neosvinčena?) Ostaja nedoločena. V tem primeru bi opazovalec lahko rekel, da je & quotA pozitivna in B negativna & quot ali & quotA negativna in B pozitivna & quot; Če je to natančen opis stanja VPP-jev, potem je vprašanje enostavno rešljivo. Ko eden od delcev pobegne v neskončnost in postane & quotreal & quot (pozitivna enrgija, ki potuje skozi vesolje), se del, ki ne uide, premakne v negativno particalno vrsto ex post facto.

Moram pa ponovno navesti, da prav to sem si izmislil v svoji zviti in ogroženi domišljiji. Upajmo, da vam bo kdo od ostalih članov povedal, ali je kje v bližini pravilno.

Termodinamika črne luknje (kvantne mikrostanje)

Fizika črne luknje stare šole meni, da je Obzorje dogodkov zapor, iz katerega ne more ubežati niti svetloba (delci brez mase). To je narobe. Zakaj? Ker Einsteinove enačbe, ki so bile uporabljene za opis klasičnih lastnosti črnih lukenj, niso upoštevale kvantne mehanike (woops!).
Kvantna negotovost in njene posledice (kot je primerno opisal v primeru Lurch) ustvarjajo kvantna nihanja v vakuumskem stanju (tj. Cikli / fluksi ustvarjanja / uničenja navideznih delcev / antidelcev). Zdaj Hawking Radiation s seboj prinaša "fantomsko podobne" Quantum Microstates (za razumevanje termodinamike črnih lukenj morate resnično sodelovati v teoriji strun). Zdaj, če predpostavimo, da se energija ohranja v kvantnih gravitacijskih stanjih, potem, ko črna luknja propade in vrže ali "izhlapi" delček, bo imel nenavadno toplotno porazdelitev.

Zdaj pa naprej iz Lurcha. Pravilno trdi, da ko en delček uide iz Obzorja dogodkov, postane "pravi" delec v našem opazovanem vesolju, antidelec pa "izgine" pod Obzorjem dogodkov. Delček, ki izgine pod Obzorjem dogodkov, ostane v "virtualnem" stanju in MORA obnoviti svoje ohranjanje energije tako, da se obdari z negativno masno energijo. Ko to naredi navidezni delček, bo Črna luknja nato absorbirala negativno masno energijo navideznega delca in zato KRČI! (zaradi posledične izgube mase). Pravzaprav lahko dejansko naredite enačbe za ta postopek tako, da preprosto določite maso črne luknje. Ko dobite njegovo maso, uporabite to formulo:

"Stopnja emisije moči (sevanja) iz Obzorja dogodkov Črne luknje je sorazmerna z obratnim kvadratom realne mase Črne luknje."
Enostavno

Vendar pa obstaja spet druga možnost, ko se razširimo na Lurch. OBE delci (delci / antidelci) lahko uidejo iz Obzorja dogodkov Črne luknje in postanejo REALNI!
Če koga zanima, ga lahko razširim.

Vendar pa obstaja spet druga možnost, ko se razširimo na Lurch. OBE delci (delci / antidelci) lahko uidejo iz Obzorja dogodkov Črne luknje in postanejo RESNIČNI!
Če koga zanima, ga lahko razširim.

Ker razdalja med njima, z veliko hitrostjo med njihovim 80 attosekundnim & quotvirtual & quot obstojem, ne pušča dovolj blizu, da bi lahko medsebojno vplivali. Torej imate dva & quotreal & delca. Od leta 2007 ni izgube energije ali & quotnegativne & quot energije maso BH upada po e = Mc 2

To si si izmislil. Za ta proces v okviru kvantne teorije polja v ukrivljenem vesolju ni nobene enačbe. LURCH je pravilen: neto energija vakuumsko proizvedenega para mora biti v QFT enaka nič, zato mora biti delček, ki uhaja s pozitivno energijo, uravnotežen z delcem, ki pada v negativno energijo. (Če se ne strinjate, predstavite izračun: rokovanje ni sprejeto.)

Za nekoliko podrobnejši odgovor na prvotno vprašanje glej:

Prvotno objavil Silverious
Mislim, da imam splošno predstavo o tem, kako to deluje.

Kako pa en delec dobi negativno energijo, ko pade v obzorje dogodkov?

Izdelava navideznih parov, ki se vrne nazaj, lahko privede tudi do tega, da se postavi neizogibno vprašanje: Kam so izginili vsi Anti-Matter?

Začenši s to izjavo Antimatter postavlja še eno uganko, ki nam jo bo pomagal rešiti LHC. Ob rojstvu vesolja naj bi bili Veliki pok, snov in antimaterija ustvarjeni v enakih količinah, vendar danes živimo v vesolju, ki je očitno v celoti narejeno iz snovi. Kam je torej odšla vsa antimaterija? Nekoč se je mislilo, da je antimaterija popolna & quotreflection & quot snovi - da če zamenjate snov z antimaterijo in rezultat pogledate v ogledalo, ne boste mogli ugotoviti razlike. Zdaj vemo, da je odsev nepopoln, kar bi lahko privedlo do neravnovesja med snovjo in antimaterijo. Povezava tukaj: http: //www.clab.edc.uoc.gr/materials/pc/dive/questions.html


Tu lahko napredujete: http: //www.superstringtheory.com/blackh/blackh3.html Upoštevajte animacijo Delca in njegovega Proti Delca. Kam so odšli vsi Proti delci?

Splošno sprejeto je, da so črne luknje temelj vsake galaksije v opazovanem vesolju, tisto, kar drži galaksije skupaj, so v galaktičnih centrih. Obstajajo dokazi, da se vsaka galaksija, če previjemo Einsteinove enačbe polja, vrne v Črne luknje v svojem jedru in že zelo zgodaj vsa Galaktična snov "lebdi" okoli Obzorja Črne luknje, zdaj po moji lastni teoriji delci, ki izhajajo iz zelo zgodnje vesolje obzorja Blackhole je dejansko velikost velikih & quotSTAR-LIKE-ENTITIES & quot; pravzaprav so zvezde.

Moramo razumeti, da naše dojemanje zgodnjega vesolja nastaja znotraj "popolnih" galaksij s polnimi zvezdami. Nekateri modeli (glavni model velikega poka) napovedujejo, da zvezde ustvarjajo črne luknje, v skladu z enačbami, ko zvezda eksplodira do določene meje, nastane ostanek črne luknje?

Blackholes ustvarjajo Stars !, ni pa to, da Stars ustvarja Blackoles. Zdaj moramo razumeti, da je pri obrnjenem modelu v enačbah polja Einsteins vesolje prostor med galaksijami in se v natančnem trenutku, na primer za našo Milkyway, ne strinja s singularnostjo celotnega vesolja, ampak samo do singularnosti Coupled Blackhole, ki je osrednjega pomena za 'našo' milkyway, to Anti-Matter postavlja v drug povsem drugačen kontekst?

Ko naša Galaksija odhaja, ostane vakuumsko polje tako kot zdaj, med drugimi galaksijami, ki so še vedno v bližini, Delci-Antidelci na enak način proizvajajo energijsko ozadje.

Torej, poenostavljeno je šla vsa Anti-snov v Črno luknjo, ki je ustvarila Zvezde, ki so oblikovale našo Galaksijo in vse druge Galaksije, ki obstajajo v vakuumskem polju, katerih gostota je temeljna za proizvodnjo Črnih luknjic oz. raztrganje Vesolja, to je skoraj popoln širijoči se sesalnik, tako kot zadrga na oblačilu, lahko včasih sprosti pritisk po polnem prazničnem obroku.


To je seveda moj poenostavljeni pogled, pri čemer sem izpustil veliko dodatnih podatkov.


Kam gre sevanje Hawking?

Preprost odgovor na vaše vprašanje je & quotnowhere & quot. Ostaja v Hawkingovi glavi. Hawkingovo sevanje je povsem konceptualni konstrukt in nima nikakršnih empiričnih temeljev.

Prijazni pozdravi
Hilton Ratcliffe
Astronomsko društvo južne Afrike.

Hilton, Lahko bi trdili, da obstaja veliko dokazov o BH: in sicer: izhodna energija kvazarjev, masne koncentracije v središču večine galaksij, rentgenske emisije Cygnus-X1 in drugih rentgenskih binarnih datotek. Zrušeni objekt Cygnus-X1 z 20–35 sončnimi masami je bil dobro kritično preučen in sklepa se, da je BH edina možnost.

Za BH potrebujete le masno koncentracijo
[tex] frac <2GM> = 1 [/ tex]
ki je lahko precej razpršen za maso reda kroglaste kopice.

Kaj se zgodi v jedru, je druga stvar. Čeprav lahko pravilno ugovarjate & quotdivide-by-zero & quot, je to odvisno od tega, kako sprejmete mejo. Ne pozabite, da se običajna diferenciacija konča z & quotdivide-by-zero & quot v meji [itex] delta x rightarrow 0 [/ itex], vendar ni problema, če je meja pravilno sprejeta.

Po drugi strani pa, če nasprotujemo temu, da je končna masa koncentrirana v ničelno prostornino, potem postavimo vprašanje: "Kaj preprečuje, da bi se vsi predmeti zrušili v ničelno prostornino?" In se zavedamo, da so odgovor notranje jedrske in em sile, ki dajejo atom in njegove sestavne dele. V singularnosti BH je videti, da gravitacija prevlada nad vsemi drugimi silami.

Ali predlagate peto silo, ki bi zdržala tako drobljivo gravitacijsko polje?

Strinjam se s tem 100% in nikoli nisem "kupil" ideje o ničelna velikost ali neskončna gostota za tako imenovano singularnost.

Mislim, da bi bila Planckova dolžina ali Planckova gostota najmanj za kakršno koli količino zrušene snovi, vendar dejansko mislite, da bi bila katera koli "naključnost" celo večja od te. Prav tako bi izključil obročno singularnost nič & quotthickness & quot. Toda ničta velikost je del opredelitev singularnosti, zato morda preprosto potrebujemo novo ime ali opis tako izjemno zgoščene snovi.

Toda, kot so ugotovili drugi, obstaja nekaj dokazov za predmete z R & lt = 2Gm / c 2. Torej, če ne potrebujemo izraza in obstoja ničelne velikosti in neskončne gostote, da sploh obstaja Črna luknja, bi potrebovali nov izraz tudi za tiste propadle koncentracije snovi .. (?) Preveč se pomeša s semantiko , vendar še vedno lahko verjamem (in še vedno verjamem), da obstajajo črne luknje, ki imajo koncentracijo snovi s končno velikostjo in veliko, vendar ne neskončno gostoto. Vsak mora to imeti v mislih zadeva / masa je v neki obliki še vedno tam in da ne samo & quot blink & quot ne obstaja. To & quotmora biti tam& quot, ali ne bi mogli izmeriti njegovega učinka (večinoma gravitacije) na zunanje predmete.

Chronos: Ali je tudi vaš komentar pomenil, da ni stisnjenih predmetov z R & lt = 2Gm / c 2, torej ni črnih lukenj ali pa samo, da ni neskončne gostote ??

10 ^ 38-krat močnejša od gravitacije. Coulombov odboj se je zlahka uprl subatomskemu gravitacijskemu kolapsu. To je zanka: gravitacija ni močna, da bi stisnila snov dovolj, da bi gravitacija postala dovolj močna. itd. Elektrofiziki Don Scott in Wal Thornhill trdita, da ko vsote končajo, celo nevtronske zvezde v resnici niso mogoče. Drugič, Oliver Manuel z univerze v Missouriju je prepričljivo pokazal, da se nevtroni med seboj odbijajo. To se še upira gravitacijskemu stiskanju in zagotavlja vir energije za kompaktne predmete. (Če potrebujete reference, jih lahko priskrbim).
Garth, postavil si zelo zanimivo točko glede diferenciacije. Račun je bil izumljen kot zelo potrebno in uporabno orodje za spopadanje s skrajnimi merili. Diferenciacija in integracija nam omogočata, da učinkovito ignoriramo neskončno majhne vrednosti. Nekaj, kar se nagiba k nič, v resnici ni nič. Psevdo tenzor ni tenzor. Delitev z ničlo je sprejemljiva le, če se približamo ničli. To lahko ločuje dlake, toda ker se prepiramo o matematičnih približkih realnosti, se moramo zavedati, da je račun do neke mere priročen. Namesto da bi ta razprava postala vaja v semantiki in neskončna izmenjava definicij, bi se raje ukvarjal s stvarmi, ki jih je mogoče opazovati ali so neposredno povezane z opazovanjem.
Kljub temu pa res cenim in spoštujem vaša premišljena mnenja.
Lep pozdrav
Hilton


"Veliki pok" ni bil eksplozija

Ko omenimo Veliki pok in širitev, je težko ne pomisliti na eksplozijo, ki je vse začela. Še posebej, ker mu pravimo "Veliki pok". Toda to je napačen način razmišljanja. Galaksije se odmikajo druga od druge, ker jih dobesedno nosi odsek samega prostora. Kot elastična tkanina se prostor razteza in galaksije se prenašajo naprej, kot zamaški, ki plavajo po reki. Torej, galaksije niso kot koščki gelerov, ki letijo stran od osrednje eksplozije. Centralne eksplozije ni. Vesolje se širi v vse smeri in je popolnoma demokratično: vsaka točka je enako pomembna. Nekdo v oddaljeni galaksiji bi videl, da se druge galaksije odmikajo tako kot mi.

(Opomba: Pri galaksijah, ki so nam dovolj blizu, obstajajo odstopanja od tega vesoljnega toka, kar se imenuje "lokalno gibanje". To je posledica gravitacije, na primer galaksija Andromeda se premika proti nam.)


Entropija in krčenje vesolja

V razmerah, ko se je vesolje krčilo, bi bil eden glavnih začetnih učinkov krčenja ta, da bi vesolje postalo svetlejše.

V našem vesolju so zaradi hitre širitve preprečili nastanek številnih velikih struktur. Če bi se vesolje namesto tega propadalo, bi dobili razvoj velikih nadgradenj, ki bi nato pogosteje trčile med seboj in ustvarjale vedno bolj masivne predmete. Verjetno bi pred časom dobili veliko več mase v črnih luknjah, črne luknje pa so konfiguracije z najvišjo entropijo končne količine snovi.

V resnici ne moremo modelirati, kaj bi se zgodilo, ko se vesolje približa singularnosti, ki se pojavi v propadajočem vesolju (poskusi obstajajo, vendar še niso dokazani). Toda bolj razkošno vesolje vesolje dobi, večja je njegova entropija. In propadajoče vesolje bi postalo svetlejše precej hitro.

kimbydov odgovor deluje v fazi sklepanja pogodb, ne glede na to, kdaj bi bil začetek. Strukture, ki so trenutno na preveliki razdalji za interakcijo, bi se začele rušiti v gostejše koncentracije.

Vendar se Big Crunch ne bo zgodil, če bo trenutni model vesolja - s temno energijo - pravilen. In ni razloga, da bi mislili, da ni. Temno vesolje, v katerem prevladuje energija, se večno širi.

Mislim, da so drugi odzivniki napačno razumeli, kaj poskušate ugotoviti s svojim vprašanjem.

To se zdi smiselno vprašanje, saj se bodo v tem obdobju gravitacijsko oblikovale nove strukture, kar bi moralo odražati zmanjšanje entropije, kot naivno razumem, saj večja struktura pomeni manj nereda. Ne razumem logike podčrtanega koncepta.

Splošno zmanjšanje entropije v resnici ni nekaj, kar se lahko zgodi v zaprtem sistemu. Če želite zmanjšati entropijo, morate imeti nekakšen vložek energije (in vir te energije se bo entropija nujno povečala za več kot zmanjšanje, ki ga povzroči).

Eden od načinov, da razumemo, zakaj je to, je upoštevanje statističnega mehaničnega ozadja termodinamike. V tem primeru je entropija opredeljena na naslednji način:
1. Ločite med & quotmacrostate & quot in & quotmicrostate & quot. "Quotmacrostate" je obsežno vedenje: lastnosti, kot so temperatura in tlak plina. & Quotmicrostate & quot je natančno stanje vseh posameznih delcev, ki tvorijo sistem. Torej ima plin okoli vas nekaj tisoč milijard milijard molekul, ki ga tvorijo, vendar ga lahko s svojim pritiskom, temperaturo in gibanjem opišemo kot svojo makrodržavo. Mikrodržava bi bila položaj in gibanje vsakega od teh tisoč milijard milijard molekul.
2. Entropija je merilo, na koliko različnih načinov lahko pomešate posamezne komponente (mikrostanje), medtem ko obnašanje v velikem obsegu (makrostanje) ostane nespremenjeno. Višja entropija = več načinov, kako lahko sestavite dele sistema, da dobite enako vedenje.

Iz te opredelitve takoj sledi, da so stanja, ki jih je mogoče mešati na več različnih načinov in še vedno ostajajo enaka večja verjetnost države. Vsi zaprti sistemi bodo s časom napredovali v bolj verjetna (in s tem višjo entropijo) stanja. In z & quotigherher verjetnostjo & quot; ne mislim niti 20% večje možnosti: za velike sisteme povečanje entropije le za malo poveča verjetnost do tako nespodobne stopnje, da lahko varno domnevate, da entropija ne bo več padla. Tako kot pri majhnem povečanju entropije bi lahko bili milijardkrat več načinov za mešanje mikrostanov, kar bi povzročilo milijardkrat večjo verjetnost.


Kaj se zgodi s krčenjem vesolja ob prisotnosti pritiska Hawkingovega sevanja? - astronomija

Ne moremo videti tistega, kar ni na našem mentalnem 'zemljevidu.' Skoraj celotno vidno vesolje je v obliki visoko prevodne plazme, vendar električnega praznjenja v plazmi ni nikjer na zemljevidu.

Rdeča supergigantska zvezda Betelgeuse, svetlo rdečkasta zvezda v ozvezdju Orion, se je v zadnjih 15 letih po navedbah raziskovalcev z univerze v Berkeleyju na Kaliforniji vztrajno zmanjševala. Polmer Betelgeuse & # 8217s je približno pet astronomskih enot ali petkrat večji od polmera Zemljine orbite. Povprečna hitrost, s katero se polmer zvezde zmanjšuje v zadnjih 15 letih, je približno 470-490 milj na uro. To pomeni, da se je polmer zvezde zmanjšal za razdaljo, ki je enaka orbiti Venere

»Ne vemo, zakaj se zvezda krči, glede na vse, kar vemo o galaksijah in oddaljenem vesolju, še vedno obstaja veliko stvari, ki jih o zvezdah ne vemo, vključno s tem, kaj se zgodi kot rdeči velikani ob koncu njihovega življenja. "
—Edward Wishnow, UC Berkeley & Laboratorij za vesoljske znanosti.

To je zadnje priznanje nevednosti o zvezdah. A vseeno bo, ker astrofiziki ne vidijo, kaj je pred njimi. Manjka večina njihovega 'mentalnega zemljevida'. To je razvidno iz drzne trditve o »vsem, kar vemo o galaksijah in oddaljenem vesolju«, večina pa je ob objektivnem pregledu znanja, ki pač ni tako. Astrofiziki z uporabo svojega staromodnega zemljevida, kako delujejo zvezde, ne bodo razrešili skrivnosti krčenja rdeče supergigantske zvezde - Betelgeuse.

Košček zvezdne perspektive

Obstaja načelo, ki preprečuje vse informacije, je dokaz proti vsem argumentom in ki človeka ne more držati v večni nevednosti. To načelo je obsodba brez preiskave.
-William Paley (1743-1805).

Mislim pod »staromodnim pogledom na to, kako delujejo zvezde«, samo gravitacijsko, samopožarno kroglico plina s termonuklearnim toplotnim motorjem v notranjosti, da jo »črpamo« do velikosti in svetlosti, ki jo opazimo. Idejo, da bi zvezdo (Sonce) lahko napajali od zunaj, je brez ustrezne preiskave obsodil pionir termonuklearnega modela zvezd Sir Arthur Stanley Eddington. Kot priča je svoje uvodne besede v Notranja ustava zvezd (1930), "Na prvi pogled se zdi, da je globoka notranjost sonca in zvezd manj dostopna znanstvenim raziskavam kot katera koli druga regija vesolja." Toda Eddington je takoj prevzel načelo, ki človeka ne more držati v večni nevednosti o resnični naravi zvezd: "Sevalna energija iz vroče notranjosti se po številnih odklonih in preobrazbah uspe boriti na površje in začeti svojo pot po vesolju." Če bi bila ta predpostavka pravilna, bi zvezde postale edina znana telesa v vesolju, ki s sevanjem prenašajo notranjo toploto. Običajno delo opravita prevodnost in konvekcija. Torej ne gre za nepomembno predpostavko, podkrepljeno z opazovanjem ali eksperimentom. Zamisel, da se zvezde napajajo od znotraj, ni prišla iz nekega znanstvenega odkritja. Ideja je stara toliko kot odkritje ognja. Predstavljen je bil kot prepričanje, kot ideološka sprevrženost znanosti.

Eddington je imel paternalističnega duha za katerega koli sodobnika tako naglo, da je nakazoval, da se zvezda lahko napaja od zunaj, in zelo dobro mu je uspelo zmečkati nadaljnje teoretiziranje v tej smeri. Toda njegovo razmišljanje je bilo napačno predpostavk, ki jih kot tak ni mogel prepoznati - na primer: "Glede na to, da energija izhaja iz notranjosti zvezde."
-Ralph E. Juergens.

Z zadnjim vpogledom je enostavno videti, da je Eddingtonov vpliv v kombinaciji s svojimi posebnimi pogledi predstavljal "mentalni zemljevid", ki ga je stoletje preusmerjal in zaviral napredek pri razumevanju zvezd. Nastanek z gravitacijskim kolapsom zvezde s supergorečim jedrom, sestavljenim iz najlažjega plina, vodika, je izjemna "Heath-Robinsonova" konstrukcija, ki temelji na izbiri neverjetnega modela s posledično malo verjetnimi predpostavkami. Na opazovalnem testu ne uspe, ker nič, kar opazimo na Soncu in nad Soncem, ni mogoče napovedati iz modela jedrske fuzije. Presenetljiva nova odkritja so zahtevala ad hoc dodatke k modelu, medtem ko številna osnovna opazovanja ostajajo nepojasnjena - na primer superhotna korona nad "hladno" fotosfero.

»Zvezda, kot je Sonce, je izjemna ... Imamo nenavaden pojav razmeroma hladnega telesa v vesolju, ki je zavito v neizmerno vročo atmosfero. (Mimogrede lahko opazimo, da je zgornja atmosfera Zemlje bolj vroča od njene površine, vendar je to manj izjemno, saj v Zemljinem primeru energija prihaja od zunaj.) "
& # 8211 prof. R L F Boyd, F.R.S., Vesoljska fizika - preučevanje plazme v vesolju, Oxford Physics Series. [Poudarek dodan]

& # 8220Znanost pogosto izbira med možnostmi. Ko se enkrat odločijo, pa se znanstveniki po navadi poenotijo ​​za sprejeto alternativo do te mere, da zanikajo in sčasoma pozabijo, da je bila sprejeta kakšna "resnična" izbira. V naslednjih učbenikih se skrivajo morebitne druge možnosti in znanost prikazujejo kot neposreden pohod po pravi poti do resnice. Ker se pozabi in zanika, da so take izbire obstajale, se rezultati teh odločitev redko pregledujejo. Ne samo, da za takšen pregled ni nobene določbe ali spodbude, obstaja pozitiven in močan pritisk med vrstniki proti takšnemu vprašanju osnovnih prostorov. & # 8221
-Don L. Hotson.

Električni model rdečih zvezd

"Večno nepoznavanje" resnične narave zvezd ni možnost. Kozmologi v plazmi so razvili preprost in skladen model nastajanja galaksij in zvezd z uporabo električne energije, ki deluje v vseprisotni kozmični plazmi. Model električnega vezja galaksij in zvezd, ki ga je predlagal Hannes Alfvén, je mogoče razširiti, da razloži zapletena magnetna polja in vidne pojave Sonca. Le disciplinska razdrobljenost 'mentalnega zemljevida' sodobne znanosti omogoča astrofizikom, da ne vidijo tega ključnega prispevka k svoji temi. Na primer, astrofiziki se sestavljajo nad "raketnimi motorji", ki so jih našli v aktivnih galaktičnih jedrih, medtem ko fiziki v kampusu v plazmi napovedujejo odkritje dvoplastnega raketnega motorja z električnim pogonom! Medtem ko je že leta 1986 na konferenci NASA o & # 8220Dvojnih slojih v astrofiziki & # 8221 Alfvén v svojem osrednjem nagovoru dejal, & # 8220Dvojne plasti v vesolju je treba uvrstiti med novo vrsto nebesnih predmetov. & # 8221 **

Eddingtonove ideje je treba obravnavati kot zgodovinsko neskladje njegove dobe plinske svetlobe, ko so svetlobo in toploto proizvajali vroči plini. Primerjajte to z našim električnim svetom, kjer se električna energija, ustvarjena na stotine kilometrov daleč, uporablja za osvetlitev naših mest in domov, in lahko vidite preprost smisel, če predlagate, da Narava deluje na enak način. Še bolj smiselno je, če razumemo, da plazma naravno tvori nevidne, a zaznavne niti kozmičnega toka, kot so naši zemeljski daljnovodi. Zvezde so kot galaktične ulične luči, ki osvetljujejo pot vesoljske električne energije, ki teče skozi galaksijo.

Elektroni z majhno maso prenašajo večino električnega toka v vesoljski plazmi. Zdi se, da so galaksije in zvezde v njih »rojeni« z pomanjkanjem elektronov z učinkovitim postopkom ločevanja naboja, ki ga opazimo v laboratorijskih razelektritvah v plazmi. Zvezde delujejo kot pozitivne anode v galaktičnem žarilnem izpustu. O rdečih orjaških zvezdah sem pisal v Twinklu, utripajoči električni zvezdi:

Rdeče zvezde so tiste zvezde, ki ne morejo potešiti lakote po elektronih iz okoliške plazme. Torej zvezda razširi površino, na kateri zbira elektrone, tako da raste velik plazemski ovoj, ki postane učinkovito zbiralno območje zvezdne anode v vesolju. Proces rasti se sam omejuje, ker se s širjenjem plašča njegovo električno polje okrepi. Elektroni, ujeti na tem polju, se pospešijo do vedno večjih energij. Kmalu postanejo dovolj energični, da vzbudijo nevtralne delce, s katerimi se trčijo, in ogromen ovoj prevzame enakomeren "rdeč sijaj anode". Postane rdeča orjaška zvezda.

Električno polje, ki poganja ta postopek, bo povzročilo tudi ogromen pretok pozitivnih ionov stran od zvezde ali, bolj znano povedano - čudovit zvezdni "veter". Takšna izguba mase je značilna značilnost rdečih velikanov. Standardna teorija zvezd tega ne more razložiti, saj naj bi bila zvezda preveč "hladna", da bi "odvrela" zvezdni veter. In sevalni tlak je popolnoma neustrezen. Torej, če ga gledamo v električnem smislu, je lahko rdeči velikan namesto blizu končne točke svojega življenja "otrok", ki izgubi dovolj mase in naboja, da začne naslednjo fazo svojega obstoja - na glavnem zaporedju.

Notranje ogrevanje ne povzroči orjaškega rdečega sijaja Betelgeuse. Gre za električni plazemski sij, kakršen vidimo v neonski cevi. In kot neonska ali fluorescentna svetlobna cev je razmeroma kul. Dejansko bodo meritve temperature (naključno gibanje) plazme v električnem polju (usmerjeno gibanje) zavajajoče, ker električno polje nagiba k temu, da gibanja poravna v eno smer. Radijske meritve porazdelitve temperature v atmosferi Betelgeuse dajejo odčitke, ki se zmanjšujejo z oddaljenostjo od fotosfere in so nižji od meritev, pridobljenih iz optičnega in ultravijoličnega (UV), kjer se temperatura izračuna iz teoretičnih vzorčnih atmosfer. Ugotovitve radijske astronomije bi lahko razložili s tokom, ki teče v radialnih filamentih v obsežnem difuznem ovoju Betelgeuseja, kot rdeči sprite, ki se raztezajo do ionosfere nad zemeljskimi nevihtami.

Velikost Betelgeuse, gledano v bolj energični UV svetlobi, je dvakrat večja od že tako velikanskih dimenzij v vidni svetlobi. Obstoj visokoenergijske UV svetlobe na velikih razdaljah nad zvezdo ustreza zunanjemu viru energije, kot je ta, ki proizvaja supergotovo sončno korono. Opažamo enak učinek plazemskega plašča, ki nepomembne kamnine v našem sončnem sistemu spremeni v komete, kot je bil nedavni komet Holmes, katerega žareča električna koma je presegla velikost Sonca. Vidni disk Betelgeuse nam ničesar ne pove o fizični velikosti osrednjega zgoščenega telesa. In kot spreminjanje velikosti komete, ko dirja proti in od elektrificiranega Sonca, rdeče orjaške zvezde spremenijo svojo velikost, da se prilagodijo svojemu električnemu okolju.

UV-podoba Betelgeuse je gladka, razen občasne vroče točke. To se precej razlikuje od UV-slike Sonca, ki ima zaradi številnih aktivnih regij običajno lisasti videz. Ta gladkost svetlobe iz Betelgeuseja je posledica precej drugačnega načina plazemskega praznjenja zatemnjenih rdečih zvezd kot svetlobnih zvezd glavnega zaporedja. To je razlika med razpršenim obsežnim sijajem neonske cevi in ​​točkovno svetlobo obločne žarnice.

Električni model svetlih zvezd kaže, da obstaja izjemno preprost nadzorni mehanizem, ki ga uvaja svetla fotosfera. Fotosfera deluje kot spojni tranzistor za uravnavanje toka toka med zvezdo in njenim okoljem. Rezultat je izjemno enakomeren izhod svetlobnega in toplotnega sevanja kljub različnim napajalnikom. Na primer, Sonce, gledano v rentgenskih žarkih, je spremenljiva zvezda. Rentgenski žarki nastajajo visoko nad fotosfero in so merilo vhodne električne energije. Razkrivajo spremenljivost sončnega vira energije. Fotosfera ustvarja sevalni izhod, ki ga stabilizira njegov tranzistorski učinek.

Zatemnjene rdeče zvezde, kot je Betelgeuse, nimajo enakega mehanizma za nadzor moči. Namesto tega se na spremembe oskrbe z električno energijo odzivajo s spreminjanjem površine svetleče plazemske ovojnice - z drugimi besedami, njihove vidne velikosti. Velikost našega Sonca se nekoliko razlikuje, kar zelo zmede astrofizike. Kar pa Betelgeuse imenujemo "fotosfera", fizično in električno ni nič drugega kot fotosfera svetlih zvezd.

Zmanjšanje premera Betelgeuseja v 15 letih kaže na počasno spremembo vhodne moči Betelgeuse. Krčenje je običajen odziv plazemske ovojnice z žarjenjem na povečanje razpoložljivosti elektronov iz galaktične plazme. Takšno povečanje je lahko posledica naraščajočega toka v lokalnem galaktičnem krogu. Lahko pa je to posledica zmanjšanja prašnosti plazme v bližini zvezde (prašni delci ponavadi odstranjujejo elektrone). Naše sonce zazna takšno spremembo skozi cikel sončnih peg in rentgenski izhod. Zdi se verjetno, da se bo Betelgeuse v prihodnosti razširila ali nihala. Prisotnost vročih točk na Betelgeuseju je treba povezati s spremembami njegovega premera.

Slika Betelgeuseove atmosfere, opažene pri valovni dolžini 7 mm z VLA. Jupitrova orbita prikazuje obseg nadvelika. Zasluge: Jeremy Lim, Chris Carilli, Stephen White, Anthony Beasley in Ralph Marson VLA, NRAO, NSF, NASA.

Z Zemlje gledamo Betelgeusev pol. The radio image of Betelgeuse is not spherically or axially symmetric. This may be explained simply by the electrical model: the current flows toward the magnetic pole, which does not necessarily coincide with the rotational pole, and out in an equatorial current sheet, which may form jets that distort the atmosphere. I believe the hot spots seen on Betelgeuse are the result of bright arc discharges or ‘stellar lightning’ near the pole. Such lightning causes upwelling of matter from the star high into its atmosphere, which would explain the warm so-called “convective cells” conventionally thought to be responsible for the hot spots. Stars do not convect heat from their interiors. Photospheric granulation is a plasma ‘anode tufting’ phenomenon.

The report states that Betelguese’s visible brightness, or magnitude, has shown no significant dimming over the past 15 years despite the star’s shrinkage. This seems odd if the bloated atmosphere were due to heating from the star. However, the electrical model may offer a simple solution. As the red supergiant’s atmosphere shrinks, the anode glow remains. It is rather similar to merely shortening a neon tube. The luminous efficiency increases with the increasing particle density nearer the star, which could offset the loss of emitting surface.

The conventional model of red supergiant stars like Betelgeuse is a story of the incredibly complicated series of thermonuclear processes that progressively “burn” through the periodic table from hydrogen through helium and on up to iron. Each process is supposed to occupy a thin shell that moves outward as the star ages. But iron is the end of the line for thermonuclear transformation: When the iron core grows so massive that the atoms can no longer resist the gravitational pressure, it collapses into a superdense state, and the star explodes as a supernova. Given that Betelgeuse is the closest red supergiant, the reported shrinkage of Betelgeuse has given rise to fears in major news media about the “dying star” and the damage it might cause on Earth if it were to explode.

Such fear is misplaced. The evolutionary story of self-immolating thermonuclear stars is wrong. Betelgeuse is merely a young star that has not achieved the kind of electrical equilibrium that comes with a bright main sequence photosphere. And supernovae are galactic “electrical circuit breakers,” not a fanciful stellar implosion followed by explosion. There is, in fact, firm evidence of external triggering of supernovae, which is shown in the non-random periodic behavior of extragalactic supernovae. Plasma physicist Anthony Peratt has noted, “Supernovae in the plasma community are viewed as the release of energy from a galactic-dimensioned filament.” And the aftermath of a supernova is clearly an axial Z-pinch plasma discharge configuration.

“Astronomers can tell the temperature of the central regions of the Sun and of many other stars within a few percentage points and be quite sure about the figures they quote.”
A Star Called the Sun, —George Gamow.

“Logic is an organised system of thought that enables you to be wrong with confidence.”
—Charles Franklin Kettering.


Inflation Theory Takes a Little Kick in the Pants

Inflation theory proposes that the universe underwent a period of exponential expansion right after the Big Bang. One of the key predictions of inflation theory is the presence of a particular spectrum of “gravitational radiation”—ripples in the fabric of space-time that are really hard to detect but thought to exist. But a team of researchers has now found that gravitational radiation can be produced by a mechanism other than inflation. So this type of radiation, if eventually detected, won’t provide the conclusive evidence for inflation theory that was once was thought to be a certainty.

“If we see a primordial gravitational wave background, we can no longer say for sure it is due to inflation,” said noted astronomer Lawrence Krauss, from Case Western Reserve University.

Inflation theory first was proposed by cosmologist Alan Guth in 1981 as a means to explain some features of the universe that had previously baffled astronomers, such as why the universe is so close to being flat and why it is so uniform. Today, inflation remains the best way to theoretically understand many aspects of the early Big Bang universe, but most of the theory’s predictions are somewhat vague enough that even if the predictions were observed, they probably wouldn’t provide a clear-cut confirmation of the theory.

But gravitational radiation was considered one of the key predictions of inflation theory, and detection of this spectrum was regarded among physicists as “smoking gun” evidence that inflation did in fact occur, billions of years ago.

Gravitational radiation is a prediction of Einstein’s Theory of General Relativity. According to the theory, whenever large amounts of mass or energy are shifting around, it disrupts the surrounding space-time and ripples emanate from the region where the shift occurs. These ripples aren’t easily detected, but there is one experiment designed to look directly for this radiation, the Laser Interferometer Gravitational Wave Observatory (LIGO) in Livingston, Louisiana. The upcoming Planck Mission, set to launch in 2009 will look for it indirectly by looking at the cosmic microwave background.

Until now it was widely believed that detecting gravitational radiation in the form of polarized light from the CMB would confirm inflation theory, since it was thought inflation would be the only way this radiation could be produced. But Krauss and his team have raised the issue of whether this radiation can be unmistakably tied to inflation.

Krauss’s team proposes that a phenomenon called “symmetry breaking,” can also produce gravitational radiation. Symmetry breaking is a central part of fundamental particle physics, where a system goes from being symmetrical to a low energy state that is not symmetrical. Krauss’s explanation is that a “scalar field” (similar to an electric or magnetic field) becomes aligned as the universe expands. But as the universe expands, each region over which the field is aligned comes into contact with other regions where the field has a different alignment. When that happens the field relaxes into a state where it is aligned over the entire region and in the process of relaxing it emits gravitational radiation.

This is all fairly confusing, but the sweetened condensed version is that if gravitational radiation is ever detected, that event won’t necessarily verify inflation theory. Therefore, whether inflation theory can ever be confirmed remains to be seen.

Krauss’s paper “Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions” is published in the Aprill 2008 Physical Review Letters.


Fascinating Question

Some of these posts are amazing. I am truly in the presence (in a digital sort of way) of some of the finest minds on the planet. Very impressive!

#52 Otto Piechowski

Another thing which I have has led to much thought is the mobius strip thinking about an actual object in three dimensional space which has only one side.

#53 FirstSight

A physical phenomenon that is indisputably real, yet inaccessibly unknowable - is what happens to matter (or equivalently, energy) once it has crossed past the event horizon of a black hole - is a black hole a true physical infinite singularity in the same sense that division by zero is a true mathematical singularity?

Consider that black holes exist because beyond a certain critical mass, neutron degeneracy pressure is no longer sufficient to prevent further gravitational collapse. The result is further concentration of mass past the threshold where the escape velocity becomes >= the speed of light, and the "event horizon" is a knowable (calculable from the known laws of physics) radius inside of which this threshold is exceeded for a specified amount of mass inside. And so, we define the "size" of a black hole by its radius (ascertainable to a good approximation by indirect evidence of radiation produced by objects swirling around just outside) and the knowable inference we can thereby make as to the amount of mass inside. However, once across the "event horizon" all information about the state of the mass inside is forever lost and inaccessible.

Here's the key "unknowable" question: is there any further sort of "degeneracy pressure" (or other sort of physical degeneracy limit) which limits mass from truly infinite collapse, analogous to the true singularity of division by zero? The "Planck length" is an inadequate answer to this question, since that merely represents the numerical size threshold below which classical (or relativistic) physics is incapable of predicting what happens, and neither can we (so far) make any quantum mechanical predictions, at least none capable of physical proof of their validity. Of course, there's the theoretical prediction that quantum "Hawking radiation" can very gradually erode the matter/energy inside the black hole - but notice that even this says nothing about whether the physical mass remaining inside continues infinitely collapsing, or whether the collapse at some concentration hits some sort of ultimate "degeneracy limit".

Even if the "Large Hadron collider" was somehow capable of producing a miniature short-lived black hole (having a harmlessly small "event horizon" relative to the scale of the apparatus) - it would still be inherently impossible to answer this question, only in part because it would be impossible to ascertain whether it dissolved before this "degeneracy limit" was reached, and in part because information about what's inside is inaccessible for the duration of conditions still making it a "black hole" rather than simply degenerate mass/energy less than any ultimate limit.

It's also important to note that any hypothesis that the mass inside a black hole might "pop out" a white hole within our own universe, or another universe - is pure pulled-from-our-butts speculation, with no provable empirical basis whatever to support it, except as plot material for science fiction.

#54 musicengin

There's some interesting explorations on this topic in the Loop Quantum Gravity research community. LQG is starting to get mentioned alongside String Theory.

In brief, they propose that matter stops collapsing when it get down to the Planck length, than which nothing can be shorter. Thus, a one solar mass black hole would stop collapsing at about 10 to the minus 12th cm across. They're calling it a Planck star.

At that point, they've calculated that it would bounce -- in its proper time, taking about a microsecond to do so in a distant observers time, about 10 billion years.

That would mean that the information would all come back out again, in a shorter time than the Hawking evaporation time.

Meanwhile, from the distant outside observer point of view, there would be a radius at which something like an event horizon would be observable -- I don't know if anyone has worked out whether such a horizon would be distinguishable from an event horizon with a singularity inside.

But Planck star approach means no information loss, over the life of the universe, and no physically impossible singularity.

And you can search on "Planck star pdf" to find refereed papers, a lot of them free for the downloading, such as the ones in arXiv.

I've been finding the reading relatively accessible, way more so than the totally impenetrable writing on string theory.

Edited by musicengin, 27 January 2017 - 12:44 PM.

#55 llanitedave

I think it was the metaphysician Thomas Aquinas who said that speech about nothing or, to say it somewhat more correctly, speaking of nothing as if it was a something is a misuse of language.

Speaking of nothing as if it were a something is the linguistic equivalent of dividing by zero. Both, in their own domains, one of speech and the other of mathematics both are are meaningless in terms of the assumptions under which the two domains operate.

These thoughts of mine (the foregoing statements don't yet address the issue which you raise of the similarities of nothingness and infinity, but perhaps by saying something true of the concept of nothing might get us into this broader discussion.

Otto

I had to share this discussion with my wife, who thought for a while and suggested: "Nothingness is the imaginary space in your brain between thoughts."

I didn't know what it means, but I liked it.

#56 FirstSight

There's some interesting explorations on this topic in the Loop Quantum Gravity research community. LQG is starting to get mentioned alongside String Theory.

In brief, they propose that matter stops collapsing when it get down to the Planck length, than which nothing can be shorter. Thus, a one solar mass black hole would stop collapsing at about 10 to the minus 12th cm across. They're calling it a Planck star.

At that point, they've calculated that it would bounce -- in its proper time, taking about a microsecond to do so in a distant observers time, about 10 billion years.

That would mean that the information would all come back out again, in a shorter time than the Hawking evaporation time.

Meanwhile, from the distant outside observer point of view, there would be a radius at which something like an event horizon would be observable -- I don't know if anyone has worked out whether such a horizon would be distinguishable from an event horizon with a singularity inside.

But Planck star approach means no information loss, over the life of the universe, and no physically impossible singularity.

There's a set of slides here that talk about this.

And you can search on "Planck star pdf" to find refereed papers, a lot of them free for the downloading, such as the ones in arXiv.

I've been finding the reading relatively accessible, way more so than the totally impenetrable writing on string theory.

For all the dense theoretical mathematics presented by this idea (and the slides)

- there is still no testable, verifiable scientific proposition being presented here.

- there is still no accessible information signal being transmitted outside the black hole by any particle or other entity once it has passed inside the event horizon of the black hole.

All that has been presented is an unverifiable prediction that a rebound "bounce" from matter reaching the purportedly incompressible "Planck Star" state will preserve the information previously lost when its constituents re-cross the event boundary (or else somehow dissolve it). Is there any reasonably suspected actual (not just theoretical) instance of such a "rebound", and if so, how could this be verifiably tested: a) either before it exited the event horizon of a black hole, or b) afterward? I saw something in the presentation about the possibility of detectable gamma-radiation being emitted in this process, in a manner which somehow preserved information about the state of matter while still inside the black hole - but by what possible means could this interpretation (or source) of the gamma radiation ever be proven?

As exotic and counter-intuitive as special and general relativity initially seemed, it was nevertheless possible to propose accessible physical instances where their validity could be definitively tested, e.g. the orbit of Mercury or gravitational refraction of starlight during solar eclipses. Where are such proposals for verifying the existence of Planck stars, or indeed whether the Planck length remains a valid limit at all inside a gravitational singularity? If there are conditions where the degeneracy pressure limits of electrons, protons, and finally neutrons can each respectively be broken past - why could this also not prove true for gravitrons or other purportedly fundamental quantum entities? Since we haven't actually found (rather than merely predicted) the existence of gravitrons, where's the actual proof that the assumption about Planck minima is actually true under the exotic singularity conditions of a black hole?

Lacking any unified theory of relativity and quantum mechanics, we can't provably predict which of their respective predictions breaks down first under sufficiently extreme conditions. Until then, we are truly still in the realm of the unknown (and unknowable and untestable).


Q: Is the total complexity of the universe growing, shrinking or staying the same?

If you were to look at the universe as an organism, was the early universe a simpler organism than the present-day organism? Is the total complexity of the universe growing, shrinking or staying the same? And how do you measure that?

Physicist: Absolutely. The total complexity of the universe is increasing, due to the inevitable march of entropy (or information), which is exactly the measure of complexity. A more intuitive way to talk about complexity and entropy is: can you predict what you’ll see next? If you look at part of a checker board, you can probably guess what the whole thing looks like, so the board is predictable and has low entropy. In the early universe matter was distributed pretty uniformly, almost all of it was hydrogen, almost everything was the same temperature, and there were no complex chemicals of any kind (going back far enough everything was ionized). So if you’d seen one part of the universe, you’ve pretty much seen all of it.

Nowadays the universe is full of a wide variety of different elements with very complicated ways to combine together, matter shows up hot, cold, as plasma, as proteins, in stars, and clouds, and not at all. The amount of data it would take to accurately describe the universe as it is now utterly dwarfs the amount that it would take to describe the early universe. On an atom-by-atom basis, in the early universe you could grab an atom at random and feel fairly confident that: it’s hydrogen, it’s ionized, it’s about “yay” far away from the other nearby hydrogen, etc. Today you’d probably be right if you guessed “hydrogen” (about 3/4 of the universe’s mass is still hydrogen), but you’d have a really hard time predicting anything beyond that.

Oddly enough, life is surprisingly un complex compared to say, dirt or sea water. If you look at a single cell in your body, you’ve already got a pretty good idea of what you’ll see everywhere else in your body. Admittedly, we are more complex than single celled life, but most of that is a symptom of being physically bigger.


Odgovori in odgovori

Not all the mass of a star need form a super-dense object. i.e. neutron star formation.
You are asking, I guess, if the huge pressure inside a very massive collapsing body could produce such high density inside that a black hole region could form which would not otherwise form by collapse from it's own mass alone? Off the top of my head: sure.
However, I suspect you are also wondering if this means that maybe such a "light" black hole could remain afterwards . that would be a no. Once formed, the light hole would quickly gobble more mass until you had a quite conventional black hole. However, this could be seen as a stage in the transition from regular degenerate matter to a black hole. probably very rapid if the transition to a Neutron star in a supernova is anything to go by.

But I didn't look anything up - there's probably a wrinkle I didn't think of right away. There may be no need, particularly in the quantum regime, for there to be an intermediate stage at all.

This is a highly speculative area after all.

Indeed. In fact, this is one of the things that makes the observed mass gap so odd. Neutron stars can be produced by O+Ne+Mg-core stars in the 8-10 M range, by Fe-core stars in the 10-25 M range, or by larger-mass progenitors if the stellar metallicity is high enough, but in no circumstance does the degenerate remnant exceed 3 M. In contrast, black holes can form from progenitors above 25 solar masses with lower stellar metallicity, sometimes involving the fallback of matter onto an initial neutron star, but in no circumstance is the black hole less than 5 M. There must be some aspect of the collapse process in which collapsing stars which meet the conditions for creating a neutron star remnant "blow away" all but <3 M to escape velocity, but collapsing stars which meet the conditions for creating a black hole remnant always manage to retain >5 M.

For two collapsing progenitors of equal mass but different metallicity, such that the first will leave a neutron star remnant and the latter will leave a black hole remnant, the former's collapse sequence must necessarily be markedly more energetic than the latter. There do not seem to be any cases in which a neutron star grows to its maximum mass and then collapses into a black hole of 3-5 M thereafter.

Well, yes, but in a less general case. Specifically, can the density gradient go up rapidly enough that a black hole of arbitrarily low mass forms?

The density/mass threshold for black holes looks like this (log plot):

If the tremendous pressure inside the center of a collapsing body causes the central density to increase more rapidly than the inverse-squared relationship between density and mass, then the black hole will start at the center at an arbitrarily low mass. I'm just trying to figure out if that's possible. It seems possible after all, in a collapse scenario where degeneracy pressure is no longer able to function, radiation pressure would be the only remaining force other than gravitational force, and the strong wavelength shifting of the gravitational field would presumably make inward radiation pressure exponentially greater than outward radiation pressure.

3 M☉) and the smallest observed stellar-mass black holes (

5 M☉) presumably, this would be the result of some aspect of the collapse sequence, but that's not really known either. . Is it possible, then, that the exponential increase in density at the center will reach the necessary conditions for the formation of a minimum-mass black hole before the conditions for a black hole are met at a larger radius, such black holes originate at the center and propagate outward? . There must be some aspect of the collapse process in which collapsing stars which meet the conditions for creating a neutron star remnant "blow away" all but <3 M to escape velocity, but collapsing stars which meet the conditions for creating a black hole remnant always manage to retain >5 M.

AFAIK, there are a few different/competing explanations for how Hawking radiation is produced. One possibility is that virtual particles arising from the quantum vacuum are boosted into existence by the gravitational field of the black hole and escape another is that mass-energy inside the black hole can tunnel through the event horizon and escape in that way. The latter explanation would seem slightly more promising, as quantum tunneling tends to fit more neatly with the whole concept of the black hole becoming more energetic as its event horizon shrinks, but then again that's just a conceptual/qualitative intuition.

Applying conceptual intuition to these things is rarely fruitful, but it's worth a short.

Let's suppose, for the sake of argument, that it is possible for a strongly self-gravitating object to satisfy the condition RS(r1)/r1 > RS(r2)/r2 with r1 < r2. In other words, regardless of how space is being curved (because that's going to mess with volume/density/etc.), the mass contained within r1 is "closer" to satisfying the conditions for a black hole than the mass contained within r2 even though r2 > r1. Let's further suppose that this condition is satisfied for all r1 < r2, so that RS(r)/r increases monotonically as r decreases. If that is the case, then during a collapse a black hole will form at the center with the currently-unknown minimum possible mass for a black hole.

What might the maths look like? Well, such a black hole may be totally outside of classical behavior and bounds, but if it does fit, then we can put some constraints on it. Its decay lifetime and Schwarzschild radius need to be greater than the Planck time and Planck length, respectively, and ideally its mass would be lower than the Planck mass.

If Hawking's equations are applicable, then the power output of a black hole is going to go to infinity as the mass decreases, so at some point the remaining mass-energy is going to become too low to sustain the required power output within its remaining lifetime. That's where I think we can tentatively put the minimum mass of a black hole. As the black hole shrinks, its temperature will also go to infinity, requiring that the peak wavelength of its blackbody spectrum goes to zero. Since the energy of a particle is defined by its wavelength, this offers a possible way to relate the energy of the discrete Hawking radiation to the total mass-energy of the black hole.

At the extreme, the micro-black-hole emits two identical Hawking radiation particles in opposite directions (so as to satisfy conservation of momentum), each containing half its mass-energy. To satisfy the blackbody spectrum, these must be emitted at the peak wavelength λ = b/TH, where b is Wien's displacement constant and TH is the Hawking temperature. However, λ = b/TH corresponds to the wavelength as seen by an observer at infinity, so we have to account for redshift. Each particle is effectively being emitted "from" the event horizon of the black hole but is leaving behind a mass distribution half the size of the black hole, and since the Schwarzschild radius is proportional to mass, the Schwarzschild metric dictates that the Hawking radiation at infinity will have a wavelength λf = sqrt(2)*λjaz, where λjaz is the emitted wavelength. Thus the wavelength of our particles is λ = b/sqrt(2)*TH, and using the equation for Hawking radiation temperature (TH = ħc 3 /8πGMkB) allows us to put this in terms of the mass:

If each of these particles contains half the mass-energy of the black hole (which we can find quite easily with E = Mc 2 ), then we can use E = hc/λ to find that λ = 2h/Mc, and we can combine this with our former equation then solve for M:

A little math, and this evaluates to 1.627e-8 kg. A black hole with mass 1.627e-8 kg, about 3/4 of the Planck mass, would have a Schwarzschild radius of 1.5 Planck lengths and an evaporation lifetime of around 6700 Planck times. 6700 Planck times is probably not enough time for this micro black hole to "suck up" anything so it is going to evaporate into those two ultra-high-energy particles before it can grow. Each of those particles has enough energy that anything they come into contact with will probably collapse into a micro black hole as well, repeating the process in a chain reaction.

I don't want to speculate too far, but if this chain reaction were to progress until the entire 5+ stellar masses had been "consumed", then perhaps collective gravitation of the whole micro-black-hole cloud would contain them, time-dilate them, and redshift their Hawking radiation so as to match the classical characteristics of a typical stellar-mass black hole.


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