Детство Вселенной глазами Планка Опции

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Детство Вселенной глазами Планка

В конце марта команда космического телескопа Планк выпустила самую точную на данный момент карту микроволнового фонового излучения [реликтового излучения] слабого, но вездесущего послесвечения Большого взрыва. Венчая приблизительно 50 лет изучения реликтового ...

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[Nils]

Хиггс наносит ответный удар?


По мнению астрофизика Стайнхарда [Max Planck Institute for Gravitational Physics in Potsdam], если на БАК не найдут новых экзотических частиц и не проведут переоценку бозона Хиггса, то у теории инфляции и всей парадигмы Большого взрыва - "большие проблемы".

Опасения Стайнхарда обсуждались, но в значительной степени были отвергнуты участниками конференции в Санта-Барбаре, в том числе членами группы миссии "Планк".

...

In general, inflationary models share the broad prediction that the range of temperature variations in the CMB should follow a Gaussian distribution, or bell curve. So far, this has been borne out by the Planck data, providing strong support for inflation. But Steinhardt and his colleagues write that the data “introduce new, serious difficulties” for the theory2.

In particular, the researchers note that as the Planck team narrowed down the list of possible inflaton fields, the models that best fit the data — known as ‘plateau models’ because their potential-energy profiles level off at relatively low energies — are far less likely to occur naturally than the models that Planck ruled out.

But the news for these plateau models gets dramatically worse, the researchers say, when the results are analysed in conjunction with the latest results about the Higgs field coming from CERN's Large Hadron Collider (LHC) near Geneva. Particle physicists working at the LHC have calculated that the Higgs field is likely to have started out in a high-energy, ‘metastable’ state rather than in a stable, low-energy configuration3.

Steinhardt likens the odds of the Higgs field initially being perched in the precarious metastable state as to those of dropping out of the sky over the Matterhorn and conveniently landing in a “dimple near the top”, rather than crashing down to the mountain’s base. Moreover, once inflation began, the quantum fluctuations generated would have quickly knocked the Higgs field off the metaphorical cliff’s edge of metastability and down to an extremely low-energy state.

In some of the old inflationary scenarios, this would not have been an issue. But in the presence of a plateau inflaton, the falling of the Higgs from its perch would cause inflation to cease too soon, cutting off the Universe's growth. The young Universe would have been more likely to curl up into black hole than to grow into a fully-fledged cosmos, Steinhardt says.

Steinhardt emphasizes that his analysis holds only because, so far, the LHC has not found any discrepancies with the standard model of particle physics. If future runs of the LHC discover exotic particles, then the energy profile of the Higgs will be recalculated accordingly. “But if you take the data we’ve been given and just follow your nose, then inflation and the whole Big Bang paradigm seem to be in big trouble,” Steinhardt says.

...

Steinhardt’s concerns were discussed — but largely dismissed — last week by participants in a programme on ‘primordial cosmology’ at the Kavli Institute of Theoretical Physics in Santa Barbara, California. Those participants included members of the Planck collaboration.

“The authors claim that the surviving models are, in their words, 'unlikely' — which is an ill-defined concept,” says Eva Silverstein, a theoretical physicist at Stanford University in California and an organizer of the programme. “The response in the discussion here was pretty much the opposite.” She notes that there are theoretically complete inflationary mechanisms that can produce viable plateau models.

“I believe most people agree that there is much more to understand about the initial conditions preceding inflation,” says Silverstein, adding that, however, “the big picture is that the Planck results are in striking agreement with the inflationary paradigm.”

Nature

Сообщение отредактировал Nils - 16.04.2013, 20:38