Teorie noua care contesta validitatea legii conservarii



A new paper by a self-described hob­by phys­i­cist chal­leng­es what may be the bed­rock law of na­ture. And while skep­tics are roll­ing their eyes, the study has ap­peared in a pro­fes­sion­al jour­nal with the ap­pa­rent con­sent of lead­ing physi­cists.
A time­line show­ing es­ti­ma­ted cos­mic ex­pan­sion since the Big Bang. Right af­ter that event, a su­per­heated, ac­cel­er­at­ing ex­pan­sion is be­lieved to have tak­en place. It lat­er slowed down. In more re­cent times, the speedup mys­ter­ious­ly re­sumed. The tilted gray disk at ap­prox­i­mate&shyly the mid­dle of the fig­ure rep­re­sents the pre­s­ent. (Cour­te­sy Law­rence Berk­e­ley Na­tio­n­al La­b­o­ra­to­ry).
The principle under dispute, central to physics for at least two cen­tur­ies, is called the law of con­ser­va­tion of en­er­gy. It states that noth­ing can be cre­at­ed or de­s­t­royed: you can’t get some­thing from no­th­ing, or vice-ver­sa, though con­vert­ing sub­s­tan­ces be­tween di­verse forms is very pos­si­ble.
But the pa­per claims new stuff may be formed con­s­tant­ly, in one spe­cial set­ting: with­in black holes or si­m­i­lar ob­jects. The idea, the auth­or adds, is tes­t­a­ble and would re­solve sev­er­al mys­ter­ies, in­c­lud­ing why the uni­verse is ex­pand­ing ev­er faster.
“Not very plau­si­ble,” though not im­pos­si­ble, was how the­o­r­e­t­i­cal phys­i­cist Ga­ry Gib­bons of the Uni­ver­si­ty of Cam­b­ridge, U.K., rated the pro­po­sal.
Cos­mol­o­gist An­drei Linde of Stan­ford Uni­ver­si­ty in Stan­ford, Ca­lif., de­clared the pa­per non­sense nine mi­n­utes af­ter be­ing e­mailed a copy. At “first glance,” he wrote back, it “does not make any sense.”
But asked to spec­i­fy its er­rors, he de­clined. The over­rid­ing prob­lem, he wrote, was not mistakes, but an over­all am­a­teur­ish­ness. “Sorry for be­ing so ne­ga­tive,” but the stu­dy is “not ev­en wrong,” he wrote—quo­t­ing a sting­ing phrase sci­en­t­ists some­times use to dis­miss ab­surd find­ings.
Yet a note pub­lished with the pa­per, in the jour­nal New As­tron­o­my this month, in­di­cat­ed it had suc­cess­ful­ly passed the scru­ti­ny of at least one emi­nent­ly qua­li­fied scho­lar: co-editor Jo­seph Silk, head of the Uni­ver­si­ty of Ox­ford, U.K., as­tro­phys­ics de­part­ment. That “does make one won­der more” about the work, vo­lun­teered Saul Perl­mut­ter of the Uni­ver­si­ty of Cal­i­for­nia, Berke­ley, one of the ac­k­now­ledged disco­ver­ers of the ac­cel­er­at­ed cos­mic ex­pan­sion. He de­clined to com­ment more on the pa­per, though, say­ing it was­n’t ex­act­ly in his field. Silk al­so de­clined.
As stand­ard prac­tice dic­tates, New As­tron­o­my ac­cept­ed the pa­per on­ly af­ter an ed­i­tor—Silk—re­viewed it in con­sul­ta­tion with an anon­y­mous out­side ex­pert, the au­thor said.
Most sci­en­tists say a stu­dy’s ac­cept­ance for pub­li­ca­tion in a “peer-reviewed” re­search jour­nal, as New As­tron­o­my is, is a mark that it con­sti­tutes se­ri­ous sci­ence. This, of course, does­n’t at all prove a study cor­rect. More­o­ver, not all peer-reviewed jour­nals comma­nd equal re­spect among sci­en­tists, and New As­tron­o­my isn’t con­si­dered the cream of the crop. Thom­son Sci­en­ti­f­ic, a Phi­la­del­phia-based or­gan­i­za­tion, rat­ed it as the 16th most in­flu­en­tial of 43 as­tron­o­my and as­tro­phys­ics jour­nals world­wide pub­lish­ing new re­search last year.
Its ed­i­to­ri­al board in­cludes, along­side Silk, re­search­ers with the Uni­ver­si­ty of Cam­b­ridge, Har­vard Uni­ver­sity and the Harvard-Smithsonian Cen­ter for As­tro­phys­ics.
For the au­thor, Greg­or Bay­er of Ce­dar Hill, Tex­as, the pub­li­ca­tion was a break­through. “It has been a very hard strug­gle for me to get an­ything pub­lished,” he wrote in an e­mail, though he had an­oth­er pa­per in print ear­li­er this year. “For­tu­nately, some good peo­ple are be­gin­ning to take me se­ri­ously.”
Bay­er at­trib­ut­ed his trou­bles to the fact that he doesn’t work for any sci­en­ti­fic in­sti­tu­tion, so oth­er re­search­ers are re­luc­tant to back his the­o­ries. “I have a Ph.D. in phys­ics from the Uni­ver­si­ty of Chica­go,” from 1972, he wrote; “but I left the field ma­ny years ago. As a ca­reer, phys­ics is hell: as a hob­by, it is heav­en. Ideas come eas­i­ly to me now.”
Bay­er’s pa­per on energy con­ser­va­tion con­si­ders black holes, stu­pen­dous­ly dense ce­les­tial bo­dies that pack so much weight in­to so lit­tle space that their grav­i­ty over­pow­ers ev­erything near­by, in­clud­ing light rays. Con­di­tions in black holes are thought to mim­ic in some ways those pre­vail­ing at the or­i­gin of the uni­verse. Then, sci­en­tists be­lieve, all mat­ter was packed in­to a point; this then ex­plod­ed in a “Big Bang,” spawn­ing the cos­mos.
If a black hole had an op­po­site, it would be what phys­i­cists call vac­u­um. In plain terms, that means noth­ing­ness, though this word is mis­lead­ing be­cause some min­i­mal lev­el of ac­tiv­i­ty has been found to un­fold even in the emp­tiest space.
Vac­u­um is ubiq­ui­tous. Even in sol­id ob­jects, there is plen­ty of room for vac­u­um, be­tween and in­side the atoms. In a black hole, vac­u­um could al­so con­ceiv­a­bly find lodg­ings. But there, the cramp­ing might be­come sev­ere even for a guest of such mod­est dema­nds—forc­ing the vac­u­um, in Bay­er’s view, to lead a pre­car­i­ous ex­ist­ence.
With­in black holes or si­m­i­lar ob­jects, he ar­gues, ex­treme con­di­tions may in­ject “in­sta­bil­i­ty” in­to the vac­u­um, con­vert­ing parts of it in­to non-vac­u­um, or mat­ter. “Mat­ter cre­a­tion can be said to arise from some new par­ti­cle in­ter­ac­tion which vi­o­lates en­er­gy con­ser­va­tion,” he wrote in an email.
Gib­bons is un­con­vinced. Bay­er fails to clar­i­fy “the dy­nam­ics be­hind” the pro­cess, he wrote, adding that stand­ard par­ti­cle phys­ics al­ready of­fers a well-sup­port­ed ac­count of how mass arises, called the Higgs mech­an­ism.
Bay­er ar­gued that some vague­ness in his ac­count is in­e­vi­ta­ble, be­cause re­search­ers are still “try­ing to fig­ure out what the vac­u­um real­ly is.”
But he claims mat­ter cre­a­tion could ex­plain the ac­cel­er­at­ing ex­pan­sion of the uni­verse, which Perl­mut­ter and oth­ers iden­ti­fied in the late 1990s. Why the speedup oc­curs is one of the most vex­ing scientif­ic mys­ter­ies of the past dec­ade. As­tro­no­mers pro­vi­sion­al­ly at­trib­ute it to a yet-to-be-i­den­ti­fied “dark en­er­gy,” whose na­ture re­mains un­known.
Bay­er’s ex­pla­na­tion of this links mat­ter cre­a­tion to anoth­er con­cept, pres­sure, a meas­ure of how much a giv­en blob of mat­ter is “squeezed” by what’s around it. It’s why your head hurts if you dive deep­ly. Neg­a­tive pres­sure is al­so con­ceiv­able—your head be­ing pulled apart—though we nev­er ex­pe­ri­ence this on Earth.
A sim­pli­fied view is that pos­i­tive pres­sure is an air hose blow­ing out­ward; neg­a­tive pres­sure, a vac­u­um clean­er suck­ing in­ward.
Ein­stein de­ter­mined that an ob­jec­t’s grav­i­ty de­pends not just on its mass, as was known be­fore, but its pres­sure. If an ob­ject has enough neg­a­tive pres­sure, its grav­i­ty can al­so be­come neg­a­tive, and hence re­pul­sive rath­er than at­trac­tive.
Bay­er ar­gued that mat­ter cre­a­tion is as­so­ci­at­ed with re­pul­sive grav­i­ty be­cause it’s al­so linked to neg­a­tive pres­sure. “The flow of en­er­gy in­to the Uni­verse can be de­scribed as be­ing caused by an ex­ter­nal pres­sure from the vac­u­um,” he wrote in an email. “Viewed from in­side the Uni­verse, the pos­i­tive ex­ter­nal pres­sure looks like a neg­a­tive in­ter­nal pres­sure.”
Bring­ing back the air-hose anal­o­gy, im­ag­ine an in­vis­i­ble hose blow­ing air out­ward and in­to the mouth of a sec­ond tube. That sec­ond pipe would ap­pear as though it were suck­ing in air—neg­a­tive pres­sure.
Neg­a­tive pres­sure with­in le­gions of black holes would cre­ate a grav­i­ta­tion­al re­pul­sion that per­me­ates the cos­mos and pushes it out­ward re­lent­less­ly, Bay­er claims. “While mat­ter is be­ing cre­at­ed, there is a grav­i­ta­tion­al re­pul­sion as­so­ci­at­ed with the en­er­gy flow. When the flow stops, on­ly the or­di­nary grav­i­ta­tion­al at­trac­tion of the cre­at­ed mass re­mains.” All new­ly minted mass would re­side perma­nently in its home black hole.
Mat­ter cre­a­tion would equate to en­er­gy cre­a­tion be­cause, as Ein­stein found with the famed equa­tion E=mc2, mat­ter and en­er­gy are two forms of the same thing.
Whatever you call it, Bay­er said the creation pro­cess could ex­p­lain not on­ly the dark en­er­gy puz­zle but an ar­ray of oth­ers: the iden­ti­ty of the “dark mat­ter” that makes up five-sixths of the ma­te­ri­al in the cos­mos, but is un­seen; why cer­tain cos­mic rays hit Earth with oth­erwise in­ex­pli­ca­bly high en­er­gies; and what caused an “in­fla­tion” be­lieved to have made the uni­verse grow stu­pen­dous­ly big with­in a frac­tion of a sec­ond af­ter the Big Bang.
Cos­mol­o­gists be­lieve ac­cel­er­at­ed swell­ing of the cos­mos oc­curred dur­ing two sep­a­rate pe­ri­ods: dur­ing the in­fla­tion ep­och, and more re­cent­ly. Bay­er says that’s be­cause both episodes wit­nessed mat­ter cre­a­tion. The speedup stopped in be­tween, he ar­gues, be­cause in­i­tial for­ma­tion of the uni­verse was over, but black holes weren’t formed yet.
Yet Linde, a found­er of the in­fla­tion the­o­ry, dis­agrees.
Bay­er said his the­o­ry of en­er­gy non-conservation could be tested us­ing par­ti­cle ac­cel­er­a­tors, which bash sub­a­tom­ic par­ti­cles to­ge­ther to help see what they’re made of. Nor­mal­ly, conserva­tion of en­er­gy is used to cal­cu­late prop­er­ties of the par­ti­cles fly­ing out of the bang-up. But the law is as­sumed, rath­er than prov­en, in these ex­per­i­ments, Bay­er ar­gued. “A se­ri­ous test of en­er­gy conserva­tion in high-en­er­gy col­li­sions will re­quire care­ful anal­y­sis of ma­ny com­plex multi-par­ti­cle events,” he wrote in his paper. This would be hard, he ad­ded, but it can be done.



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