
A Crisis at the Edge of Physics - RyanGWU82
http://www.nytimes.com/2015/06/07/opinion/a-crisis-at-the-edge-of-physics.html
======
mahranch
What this article fails to take into account is the underlying politics at
play here. You might think of all places, that science would be "politics
free" but it's not. Far, _far_ from it.

For example, people working on string theory and people working on say,
quantum loop gravity are somewhat at odds with one another. String theory may
not see the QLG people as a direct threat but the QLG people _certainly_ sees
string theory as competition. Now you may wonder, "In competition for what?"
and the answer to that is a bit more obvious: Funding (money for research and
their very own paychecks) and attention from their peers/media/press/etc.
These people's very livelihoods are at stake.

If QLG was proven wrong tomorrow, it's not like the people who were doing that
for the last 15 years can just jump into another field. There's plenty of
incentive for "hostile science" as I like to call it. There have been some
well-known physicists who have written entire books bashing their competition
for this purpose (See: Peter Woit's "Not Even Wrong", which incidentally, is
chuck full of so many inaccuracies someone else wrote a book disputing his
book...)

So when I see articles like these, I like to check out who the author is. Do
they have a reason to write this piece? In this case, it's Adam Frank and
Marcelo Gleiser. Both are coincidentally astrophysicists at very respected
universities. I wonder what they're working on?

It appears Marcelo Gleiser, one of the authors, just published an anti-String
theory book which claims that "We don't need a Theory of Everything".

~~~
DennisP
Yes, but it's possible that the points they raised were the reason they took
that side of the debate. I don't think it's really useful to question people's
motives, rather than just considering their arguments.

~~~
Retra
You can easily hide bias behind good arguments. Attention to motive is how you
discover this bias. Humans are notoriously awful at dealing with bias, and
you're suggesting that people remove one of the only tools they have against
it?

~~~
DennisP
It's often very difficult to determine another person's actual motives are. In
this particular case, there's no way to know whether someone takes a side
because of their bias, or has a bias because their honest opinion led them to
invest a personal stake in it.

If the arguments are actually good, it doesn't matter what motivated a person
to make them. Casting aspersions on motive is just a cheap way people avoid
dealing with good arguments they don't like, perhaps because of subtle biases
of their own.

------
jamesrcole
The article fails to clearly distinguish two issues: what we take to be true,
and what we choose to work on for the moment.

We need evidence backing up what we take to be true.

But we can and must be able to work on ideas without evidence for their truth.
We must be given time to flash them out, to try and find ways to get evidence
for them.

Wanting to pursue a possible explanation is not the same as believing that
it's true.

~~~
kijin
Exactly.

Many of the people who work on string theory obviously believe it to be true
in one way or another; it's hard to stay motivated otherwise. But the rest of
the world need not care whether it is true or not. For the time being, it's
just one untested hypothesis among many.

It can take years (or even decades) for a theory to grow to the point where it
can produce testable hypotheses, and more decades (sometimes even centuries)
to test those hypotheses. This is especially true for theories that deal with
extreme scales of space and/or time, such as cosmology, geology, paleontology,
and (at the other extreme) anything that deals with subatomic particles.

Gravitational waves [1], for example, have been predicted for almost a century
now, but we still don't seem to know how to build a machine to detect them.

The last time this topic came up, I wrote a response titled "Why so
impatient?" I'll leave the link below [2] in case anyone is interested.

[1]
[https://en.wikipedia.org/wiki/Gravitational_wave](https://en.wikipedia.org/wiki/Gravitational_wave)

[2] [https://www.kijinsung.com/post/why-so-
impatient](https://www.kijinsung.com/post/why-so-impatient)

~~~
glaberficken
Really liked your article =)

Long term thinking is really hard to do these days.

I'm 36 and my generation seems to take for granted that everything evolves at
the same pace as most 20th century technologies have done so far.

This seems to be compounded by the prevalent market driven logic that
prioritizes short term profit above all.

Putting these things in their correct historic timescale is very insight-full.

thank you =)

------
Animats
This is mostly a problem with string theory. Here's a popular version of a
critique.[1] Smolin's 2006 "The trouble with physics" is a book-length
critique of it. Peter Woit' s "Not Even Wrong: The Failure of String Theory &
the Continuing Challenge to Unify the Laws of Physics" is even more critical.

It's been a decade since that, and the experimental evidence for string theory
remains nonexistent. As Fred Hoyle once wrote, "Science is prediction, not
explanation". A theory with no experimental support cannot lead to usable
technology, either.

Fundamental physics is currently stuck. There's a lot of denial about this.
There's a whole generation of string theory faculty in senior positions.
That's the problem.

[1]
[http://www.theguardian.com/science/2006/oct/08/research.high...](http://www.theguardian.com/science/2006/oct/08/research.highereducation)

~~~
TheOtherHobbes
I know someone with a PhD in string theory. He eventually left the field - not
just because it was (as he put it) "mostly bullshit", but because the
popularity of the field was based on distortingly aggressive academic PR and
self-promotion by rather too many researchers in the string theory community.

The other problem for physics is that so much of the talent works on Wall St
doing things that are - for all practical purposes - useless, if not
counterproductive.

So physics is stuck for two reasons, and won't start moving again until the
culture changes enough to fix both problems.

Given the declining (political) value of long-term theoretical research in
academia, and the relative impossibility of doing an original PhD exploring
ideas outside the mainstream, I'm not expecting change any time soon.

This is beyond tragedy, because in terms of medium-term human survival,
_nothing_ is more important than new science.

------
jordanpg
This article strikes me as having lost its focus in editing somehow.

One can hardly blame theoretical physicists for exploring above and beyond
what the experimentalists are doing. It's not like there's a large body of
more practical, down-to-earth problems being ignored in favor of these sexier,
Nobel-bait questions.

I believe the point is that we are in trouble if something exciting doesn't
happen at LHC; in this case, getting the _planet_ to fund an O($1T)
accelerator to probe higher energy levels seems far-fetched. Theorists know
this. This is a closely related point to the comment about the politics of
theory.

I don't know that this automatically spells crisis. There are plenty of
problems out there that require the mathematical talent of folks that can
perform at this level. Eventually, when more data is available, the pendulum
will swing back towards interesting theory.

After all, it's not the case that if there isn't some rush to a GUT before
2020, the human race loses.

~~~
nn3
Modern physics currently cannot explain what most of the universe is made of,
as in the dark matter problem. While not exactly "down to earth" this would
seem like a very pressing problem to me, that may be in need of more
attention.

~~~
jordanpg
While I am as convinced as you about the urgency of these issues _in the
context of physics itself_ , a crisis it is not. Not for physicists and
certainly not for civilians.

~~~
aminorex
You say that now, but when your sailboat gets eaten by a dark matter kraken
you will sing a different song.

------
javajosh
This is very frustrating for those of us that see the rather large problem in
front of us - our apparent total inability to move around the stars, and only
feeble ability to move around our solar system. This caps the lifespan of
humanity (and most of the life we know) at about 500k years at best. So, even
if we succeed wildly at our environmental and social problems, we'll end up
with a single beautiful world getting smashed to bits by a meteor, gamma
burst, or other uncontrollable, unavoidable cosmic event.

Physicists need to get their heads out of their political/philosophical asses
and start earning their bread - which is nothing less than to justify our
technological existence by discovering the knowledge that will help our
species live longer. If not for this, I think we'd all be better off living on
a planet of 200M people living in rural villages, leading simple lives that
are as happy and fair and erudite as fate and culture allows.

~~~
drjesusphd
Plenty of us are working on nuclear fusion, but funding keeps getting cut year
after year. It's simply not as sexy and doesn't get as much attention as the
cosmological kinds of questions.

------
loup-vaillant
There's a difference between the epicycles and the multiverse (assuming we're
talking about quantum decoherence, I don't really know about the others). See,
the epicycles really were additional entities, and therefore a problem, with
respect to Occam's razor.

Quantum decoherence is different: it merely follows the equations, and do
_not_ posit any additional entity on top of them (such as a collapse). The
consequence of removing that entity is multiple universes, but so what?

The problem with science is that it tends to favour the _first_ theory that
fits the fact. Instead, it should favour the _simplest_ theory that fits the
fact.
[http://lesswrong.com/lw/qa/the_dilemma_science_or_bayes/](http://lesswrong.com/lw/qa/the_dilemma_science_or_bayes/)

~~~
sriku
I thought the multiverse "theory" the article talked about was not the many
worlds interpretation of quantum mechanics, but the proposal that multiple
universes are exploding like bubbles with the boundary of each expanding at
the speed of light so no communication between them is possible. No?

You do bring up a valid point about occam's razor - i.e. It is a valid effort
to come up with a strictly simpler theory that can explain already known
observations than what is currently accepted. "Simpler" in the sense of fewer
assumptions being needed. The difficulty is that we're often blind to the
assumptions we're making in our theories and it can take a while for those to
surface.

~~~
JoeAltmaier
I wonder if that isn't essentially 'overfitting the data'. Any bounded data
set can be modeled simply. But it doesn't predict anything. A useful theory
would beget testable hypotheses.

~~~
sriku
They're not quite the same when it comes to physics, where you have the
additional characteristic of _precision_ for theories. For a trivial example,
"anything can happen anywhere at any time" certainly covers all observations
and is simpler, but has no precision in what it forbids.

Any new theory in physics must have at least the same precision as the known
theories. The problem in current physics-at-the-edge (raised by the article)
is that these newer theories are coming up with so many ways in which
universes can be formed that even though we're moving in the "simpler"
direction by relinquishing fundamental some assumptions, we're losing
"precision" in this sense. This is now happening to the extent that the very
notion that the job of a scientific theory is to only explain the _observable_
universe is being called into question and theories that consider our universe
to be just one of many universes with different parameters are also included
in the play. At that point, the working assumption that all these universes
that our mathematics invents actually exist though we cannot observe them, is
a simpler view of the cosmos ... until we know better. However, the practical
utility of such an expansive theory ends up being limited relative to the
theory that it is trying to replace, since our ability to predict things in
_our_ universe is not being improved on.

edit: What I'm trying to say is, I guess, that "precision" and "simplicity"
are opposing forces that keep a check on overfitting.

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coldcode
I wonder if our understanding of the universe will ultimately exceed our
ability to reason about it. Complexity can increase without bound but our
brain's capacity to understand and model isn't increasing at all. Maybe we
should find some way to make smarter physicists.

~~~
escherplex
Very Zen. The failure to recognize the limitations of one's received cognitive
instrumentation. And this instrumentation is empirically oriented so without
empirical validation what have you got? And with emphasis placed on theories
which are 'sufficiently elegant and explanatory' while setting aside the need
for experimental confirmation merely sets the theorist up for 'The great
tragedy of Science — the slaying of a beautiful hypothesis by an ugly fact'
(Thomas Huxley)

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ISL
Experiment is the arbiter of truth.

Without it, how could you know what's true?

~~~
lnanek2
For most professionals in this field, what's true is pretty irrelevant. Only
what brings in funding is what matters. That's why unprovable theories have so
much success. It's much better to have something no one can prove wrong and
destroy your career than have something that can be. Newton was proved wrong
by Einstein, after all, being shown to just be an approximation compared to
relativity. So the next step forward is to make sure your theory can't suffer
like that and dry up your funding. The next step forward for these people
isn't more accurate models and truth, it is more fundable ones.

~~~
ISL
I am a professional in the field :). I make precision experimental tests of
gravity.

If a line of physical theory never leads to something testable, is it a
physical theory?

Elegance and beauty are major guiding lights for theory, but they can't be the
end goal if our desire is to learn the nature of Nature.

Arkani-Hamed and others chasing the physical utility of the Grassmanian are a
modern example of beautiful mathematics straining toward physically-testable
theory. I expect you'll see more money flowing that way in the next few years.

