Excerpt from huffingtonpost.com
I am a huge science enthusiast and an unabashed science fiction fan.
There are tons of really cool stories out there that fire the
imagination and even inspire young people to go into science. (I know
they did me.) But I also know the difference between fiction and fact
and there is a clear distinction between the two. Fudging that boundary
cheapens real science.
If you’re a science geek and internet
denizen like me, you’ve encountered a lot of stories over the last few
days with titles along the lines of “LHC scientists poised to discover
parallel universes.” And that’s just wrong. It completely
misrepresents an otherwise reasonable physics article published in the eminently reputable journal Physics Letters B.
“Absence
of black holes at LHC due to gravity’s rainbow,” written by Ahmed Farag
Ali, Mir Faizal and Mohammed M. Khalil, describes a speculative idea to
explain why black holes haven’t been observed at the LHC. But to
understand their paper, you first have to understand why black holes at
the LHC were a possibility.
One of the biggest mysteries in modern
physics is why gravity is so much weaker than the other known
fundamental forces (electromagnetism and the strong and weak nuclear
forces). While we have no real idea why this is true, one idea was
proposed is that there exist more dimensions of space than the familiar
three in which we live. If the other three forces are constrained to
three dimensions, while gravity can spread into others, then maybe the
weakness of gravity is an illusion. Maybe gravity is just as strong as
the other forces, but appears to be weak just because it “has more
places to go.” I made a video that explains this better.
Now
we know that this idea has issues, because Newton’s Law of Gravity
tacitly presupposes three dimensions and we are able successfully launch
probes to distant planets. Ordinarily, that would kill this whole
idea, but there is a loophole. Suppose that these additional dimensions
of space were just very small, say smaller than an atom. Then the
astronomy argument wouldn’t hold and maybe the extra dimension idea is
saved.
So how would you demonstrate these extra dimensions? Well
the easiest way would be to study very small things. When you started
studying things that were about the size of the extra dimensions, then
you’d be entering the realm where gravity is strong. And if gravity is
strong and you concentrate enough energy, you will make a microscopic
black hole. Thus searching for microscopic black holes is a serious
scientific proposition because if we find them, we’ve also found extra
dimensions.
Scientists looked for black holes in the data taken by
LHC scientists during the 2010 – 2012 running period and none were
found. From that observation, scientists were able to set limits on the
maximum size of additional dimensions.
The paper of Ali et al.
explores how one can retain “bigger” extra dimensions (where bigger
still means subatomic in size), given the non-observation of black
holes. What they argued was that an effect was overlooked in which a
deformation of space by quantum gravity would change the size at which
black holes would form. If their idea is true, it might be that we have
to look for objects smaller than the new dimensions to see black holes.
Now
this paper might be right or wrong, however the connection with
parallel universes is entirely misleading. People think of parallel
universes like the Dr. Who episode “Doomsday” in which the
Doctor and his companion were marooned in separate, but parallel,
universes. (See, I told you I was a science fiction geek.) And that’s
just not true.
Black holes are the signature of subatomic extra
dimensions, not parallel ones. Plus remember that these extra
dimensions are ones from which electromagnetism and the strong and weak
nuclear forces are excluded. So there is no possibility of making atoms
there. Further, since these extra dimensions must be smaller than a
proton, that’s another strike against the possibility of anything
resembling ordinary matter in them.
In short, the title of these
articles is entirely misleading. And that’s a shame, because the idea
of extra dimensions is already incredibly exciting. It would mean that
we would have to rewrite our textbooks. But there is no reason to
cheapen such a momentous discovery with sensationalist and incorrect
science.
These articles will eventually disappear, hopefully into
oblivion. In the meantime, don’t get caught up in the misleading hype.
Instead, keep your eye open for >>real<< scientific
measurements from the LHC. They will be exciting enough.
Source Article from http://feedproxy.google.com/~r/AscensionEarth2012/~3/3F6BGKnkL1I/the-truth-about-black-holes-large.html
Black Holes, the Large Hadron Collider, & Finding Parallel Universes
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