Weakly interacting massive particles (WIMPs) are the top candidates for dark matter, the invisible stuff that makes up about 84% of the universe’s matter. But two recent experiments designed to sniff out the elusive particles have come up empty-handed, calling previously promising results into doubt.
The Planck space observatory was shut down for good on Wednesday, ending the satellite’s four-and-a-half-year stint observing the relic light of the Big Bang, in the greatest detail yet obtained. A shutdown signal transmitted yesterday cut off the satellites transmitters, and previous signals had sent Planck coasting away from the L2 Lagrange point a million miles from Earth that had been its home since its launch. (A Lagrange point is a point of gravitational balance near the Earth, or another space body, where objects can remain in place indefinitely. Placing Planck there allowed it to remain relatively near the Earth while also being permanently on the dark side, away from the interference that would have been created if it had orbited nearer.)
But just because Planck itself has been put to rest, doesn’t mean it has nothing left to give. The first release of Planck’s CMB data came in March; another more detailed release is set for next year. The data have already allowed more precise measurements of the universe’s age (13.82 billion years) and clarified conditions in the early cosmos.
At the other end of the scale, this year’s Nobel Prize for physics went to Peter Higgs Francois Englert for the LHC’s detection of the Higgs boson. The Higgs is the last major element of the “Standard Model” of physics, and its discovery supports the Model’s correctness. But the trouble is that the LHC hasn’t found anything else particularly noteworthy that could give a clue as to which direction to pursue next.
Laura Mersini-Houghton writes in the latest issue of Nautilus in defense of the multiverse, offering, she says, empirical evidence for it. Her claims are, needless to say, controversial. Yet I would say that she has, at least, the right approach in spirit: if the “multiverse” is accepted, it should be on the basis of the observed, empirical evidence. So I leave aside for the moment the question of whether these observations are in fact evidence of the multiverse, and look at some more fundamental questions.
There are two basic mistakes that can be made regarding the multiverse:
(0) Actually, there are three mistakes, and the underlying one is to misunderstand the word “multiverse” in the first place. I’m not a fan of it. If the basic idea is correct, it just means that the universe extends beyond the “Big-Bang-begun” region that we inhabit. It is, nevertheless, a single, causally connected whole in the relevant metaphysical sense, and the “multi” part of the multiverse can thus be misleading. If the multiverse is empirically observed, it is not empirical observed evidence of more than one ontologically independent universe (which is impossible, as entirely independent universes are, by definition, unobservable), it is rather just empirical observed evidence of a bigger universe.
(1) To get to the more mundane mistakes, then, the first is to accept the multiverse as an apparent way out of the puzzle of the universe coming from nothing or being dependent on a Creator. Some think that if they can show that the Big Bang was caused by some prior physical cause, God is eliminated. This won’t work, because even if the multiverse theory is correct, every one of the classical arguments for the Creator still stands. The multiverse theory just makes the universe bigger and older; it doesn’t change its ontologically contingent status.
(2) Similarly, the second mistake is to reject the multiverse just because some people use it as an attempt to avoid the conclusion of a Creator. Those who do the latter do so erroneously; therefore, it does not follow that the multiverse is wrong. If it is wrong, it should be shown so on the basis of sound scientific reasoning, not because some people philosophically misinterpret it.
So, yet again, for the most fundamental theological and philosophical questions, the multiverse is simply irrelevant. It may be scientifically true, and thus interesting, or it may be a dead end, but it is up to science to show us, and philosophers and theologians need not be too troubled.
I seem to have missed this interesting post last month at First Things in which Stephen Barr mentions his own small role in working out the possible significance of the finding of the Higgs boson, with its particular properties, and with reference to a more in-depth article here at Scientific American.
“My motivation to organize this conference and to edit the book was to discuss the idea that science today is compatible with phenomena governed by non-material principles like, for instance, free will and consciousness. This idea is supported by experiments demonstrating the so called quantum nonlocality, in particular two experiments I proposed in the years 1997 and 2010. These experiments have been realized in the lab of Quantum Optics at the University of Geneva by Nicolas Gisin and his Group, and the results have been published (2002, 2003, and 2012). The experiments confirm that quantum phenomena cannot be explained by invoking only material influences, that is, signals propagating in space-time. And what is more, the basic principles ruling the material world like the conservation of energy require a non-material coordination, otherwise they would not hold.”
This is the most detailed view yet obtained of the cosmic microwave background, the light that was released after the universe finally settled down enough for the first atoms to form and for light to travel unimpeded through space. This image, released at the end of March, was produced with data from the ESA’s Planck space telescope and shows the most precise map of the slight variations present in the microwave background.
“An extreme pair of superdense stars orbiting each other has put Einstein’s general theory of relativity to its toughest test yet, and the crazy-haired physicist still comes out on top.
About 7,000 light-years from Earth, an exceptionally massive neutron star that spins around 25 times a second is orbited by a compact, white dwarf star. The gravity of this system is so intense that it offers an unprecedented testing ground for theories of gravity.”
Read the story at Space.com, or in the video above-–you do have to wait through the commercial, though.
and the University of Queensland is still performing the world’s slowest experiment.
Links: NewScientist, Catholic Herald, and University of Queensland
Image: University of Queensland
If you thought Einstein was all settled, there’s still a few wrinkles to work out. For instance, John Farrell is taking a look at the equivalence principle and new attempts to figure out just what’s going on when we say that acceleration and gravity are physically indistinguishable…
…and a scientist who claims to have found a contradiction between relativity and electrodynamics has stirred up some responses…
…and, just for fun, if you think that the Galaxy is just good for pretty pictures and intellectual puzzles, you’re clearly not a dung beetle.
Dark Universe: NASA and ESA join forces to tackle the great mysteries of dark matter and dark energy;
…while meanwhile, the mysterious shrinking of the proton remains unexplained.