Are there any unsolved physics problems?

[John_Williams]

I was curious if there were any unsolved physics problems and if so which is the most important or intriguing. I have been meaning to contribute to the scientific field in some capacity and I think solving an unresolved issue in physics could do just that. Thanks!

 

[anorlunda]

@shyboy posted this here in 2005. When you are finished solving these, post here again and we'll give you some more.

Here is the list proposed by a Nobel laureate V. Ginzubrg
1. Controlled nuclear fusion.
2. High-temperature and room-temperature superconductivity.
3. Metallic hydrogen. Other exotic substances.
4. Two-dimensional electron liquid & the anomalous
Hall effect and other effects.
5. Some questions of solid-state physics & heterostructures
in semiconductors, quantum wells and dots,
metal-dielectric transitions, charge- and spindensity
waves, mesoscopics.
6. Second-order and related phase transitions. Some
examples of such transitions. Cooling sin particular,
laser cooling to superlow temperatures. Bose-
Einstein condensation in gases.
7. Surface physics. Clusters.
8. Liquid crystals. Ferroelectrics. Ferrotoroics.
9. Fullerenes. Nanotubes.
10. The behavior of matter in superstrong magnetic
fields.
11. Nonlinear physics. Turbulence. Solitons. Chaos.
Strange attractors.
12. X-ray lasers, gamma-ray lasers, superhigh-power lasers.
13. Superheavy elements. Exotic nuclei.
14. Mass spectrum. Quarks and gluons. Quantum chromodynamics.
Quark-gluon plasma.
15. Unified theory of weak and electromagnetic interactions.
W± and Z0 bosons. Leptons.
16. Standard Model. Grand unification. Superunification.
Proton decay. Neutrino mass. Magnetic monopoles.
17. Fundamental length. Particle interaction at high and
superhigh energies. Colliders.
18. Nonconservation of CP invariance.
19. Nonlinear phenomena in vacuum and in superstrong
magnetic fields. Phase transitions in a vacuum.
20. Strings. M theory.
21. Experimental verification of the general theory of
relativity.
22. Gravitational waves and their detection.
23. The cosmological problem. Inflation. The L term
and “quintessence.” Relationship between cosmology
and high-energy physics.
24. Neutron stars and pulsars. Supernova stars.
25. Black holes. Cosmic strings.
26. Quasars and galactic nuclei. Formation of galaxies.
27. The problem of dark matter & hidden mass and its
detection.
28. The origin of superhigh-energy cosmic rays.
29. Gamma-ray bursts. Hypernovae.
30. Neutrino physics and astronomy. Neutrino
oscillations.
V. L. Ginzburg
Rev. Mod. Phys. 76, 981-998 (2004)
or

Vitalii L Ginzburg, "On some advances in physics and astronomy over the past three years ", Phys. Usp., 2002, 45 (2), 205-211.

'But my favorite was this:
"What happens to all those pens, and socks?"

--Chi Meson

Edit: Also check the list of similar thread titles at the bottom of this page.

 

[Astronuc]

The Most Important Scientific Problems Have Yet to Be Solved​

https://thereader.mitpress.mit.edu/the-most-important-scientific-problems-have-yet-to-be-solved/

I just happen to come across the article a couple of days ago, but the article was first posted on Jan 6, 2020. It would seem relevant still.

 

[malawi_glenn]

15. Unified theory of weak and electromagnetic interactions.
W± and Z0 bosons. Leptons.

15. Well the Higgs boson was discovered in 2012, so I do not know really if that is what Ginzburg had in mind?

21. Experimental verification of the general theory of
relativity.
22. Gravitational waves and their detection.

21. what expeirmental verification? There have been several experimental verifications of GR https://en.wikipedia.org/wiki/Tests_of_general_relativity
22. Done in 2015 (indirectly from Pulsars in the 1970's - Nobel prize 1993)

 

[TeethWhitener]

Two things about that list: 1) it was written 20 years ago, and 2) it was written by a man in his late 80s.

As a result, I’d say very few of the items on that list can still be regarded as “unsolved,” with some having essentially been solved well before the list was written (fullerenes were discovered in 1985, for instance, and the Nobel was awarded in 1996–I worked on fullerenes in the late 2000s as a grad student, when it was already a dying field).

One wide open area that basically didn’t exist at the time of Ginzburg’s list is the statistical mechanics and thermodynamics of active matter. A lot of really interesting work is being done in this area, with crossover into nanoscience and biophysics (the latter of which is conspicuously absent from Ginzburg’s list). Just my 2 cents.

I have been meaning to contribute to the scientific field in some capacity and I think solving an unresolved issue in physics could do just that.

I like your alacrity, but prepare to be disappointed. You will go further by pursuing work you’re interested in, without regard to the prestige of the problem you’re solving, than by the converse.

 

[gleem]

and 2) it was written by a man in his late 80s.

and your point?

 

[Vanadium 50]

and your point?

I don't know what his point was, but one good point was that his perspective was formed 50 or 60 years before, so could be up to 80 years old.

 

[malawi_glenn]

Two things about that list: 1) it was written 20 years ago, and 2) it was written by a man in his late 80s.

I know that, but the list was posted as a serious response to OP's question.

 

[Maarten Havinga]

Why the Standard Model of particles? And not something else?

 

[malawi_glenn]

Why the Standard Model of particles? And not something else?

Could you elaborate on the question? Do you mean why the standard model is THE way we describe particle physics, or do you mean why it is on that list?

The standard model is quite a bad name, it is really called the Weinberg-Glashow-Salam model. Let's say we find another particle which was predicted by model "X". Five or so years from the discovery of such, model "X" will be called the standard model.

 

[pinball1970]

Sorry Slight tangent- I read his list (metallic Hydrogen?? What?)

As a non-physicist I think I could have a good crack a few big ones from spending so much time on here

The phrasing would be non- technical but I absolutely have to have a go at this!

My list

What happened at T=0?

Was there a T = -1? -2? etc

What is the solution to the flatness problem?

Is inflation correct?

Is the universe spatially infinite?

Is the universe temporally infinite

Why are there no monopoles?

Where is all the anti- matter?

Are there supersymmetric particles ?

Is string theory (version of) correct?

Is there a single fundamental particle?

What is solution to the Hubble problem? Tension? What’s the solution?

What is required to unify QM and GR?

What happens inside a black hole?

What is a measurement?

What is an observer?

What is the correct interpretation of QM?

 

[malawi_glenn]

I have been meaning to contribute to the scientific field in some capacity and I think solving an unresolved issue in physics could do just that.

Are you saying you are going to do "research" on your spare-time or are you thinking about where to apply for grad-school?

 

[ohwilleke]

Many properties of neutrinos are not known including how neutrino mass arises.

The cause of the phenomena attributed to dark matter is not well understood.

 

[otennert]

I was curious if there were any unsolved physics problems and if so which is the most important or intriguing. I have been meaning to contribute to the scientific field in some capacity and I think solving an unresolved issue in physics could do just that. Thanks!

The things that immediately come to my mind are (far from exhaustive of course):

1. quark confinement: how to derive this from QCD?
2. what does any sort of "quantum gravity" look like? In any case: how to merge quantum theory and gravitation?
3. is there dark matter? What is its nature? do we actually really need it?

 

[malawi_glenn]

Many properties of neutrinos are not known including how neutrino mass arises.

I don't understand people who say "we understand the standard model"... poor little neutrinos ν We don't even know if they are Dirac or Majorana!

 

[Fra]

which is the most important or intriguing

I think normally as you study physics and build your own understanding, you will see what questions that are most important and intriguing for you, which may well be different than that others think.

/Fredrik

 

[pinball1970]

@shyboy posted this here in 2005. When you are finished solving these, post here again and we'll give you some more.'But my favorite was this:
"What happens to all those pens, and socks?"

--Chi Meson

Edit: Also check the list of similar thread titles at the bottom of this page.

After a search through the literature I can confirm that the pen problem (sometimes referred to as "the pen question." Where the hell is my pen!? That's two in two days!) was actually solved in 1978 by Douglas Adams.

“Somewhere in the cosmos, he said, along with all the planets inhabited by humanoids, reptiloids, fishoids, walking treeoids and superintelligent shades of the color blue, there was also a planet entirely given over to ballpoint life forms. And it was to this planet that unattended ballpoints would make their way, slipping away quietly through wormholes in space to a world where they knew they could enjoy a uniquely ballpointoid lifestyle, responding to highly ballpoint-oriented stimuli, and generally leading the ballpoint equivalent of the good life.”

 

[gmax137]

I'd like to find the planet of the 10mm sockets.

 

[Grelbr42]

The sock problem is long solved. They cling to the inside of the dryer due to static. I go to laundromats and check the dryers. Checking ten dryers can often net you three or four unmatched socks. All freshly laundered.

 

[pinball1970]

The sock problem is long solved. They cling to the inside of the dryer due to static. I go to laundromats and check the dryers. Checking ten dryers can often net you three or four unmatched socks. All freshly laundered.

It's someone else's socks though. Someone else's feet ..

 

[nightvidcole]

Yes, many unsolved problems. Our current models are limited in scope since experiments can only test up to certain energies and certain length scales. Our knowledge of the extremely large (cosmology, dark energy, etc.) and the extremely high energy (beyond standard model energy scales) is very limited. No one knows what happens beyond the cosmological horizon, what happened 1 femtosecond after the big bang, if other universes exist, or what happens when you smash particles together at 10^26 eV. We have no way to test any of that. We also have no way to test for extremely low mass particles that do not interact appreciably with normal matter. We could have many different kinds and have no clue.

 

[Jodo]

You could try to figure out what space is actually made of. That would be an awesome contribution.

 

[phinds]

The sock problem is long solved. They cling to the inside of the dryer due to static. I go to laundromats and check the dryers. Checking ten dryers can often net you three or four unmatched socks. All freshly laundered.

Yes, BUT ... what you're not pointing out is that those socks were magically transmitted from another city or country which is where they were lost in the first place. OUR socks get the same treatment and end up elsewhere.

 

[gmax137]

Pair reduction -- It's the opposite of pair production.

 

[Drakkith]

You could try to figure out what space is actually made of. That would be an awesome contribution.

You're assuming that space is actually made of something. Big assumption.

 

[Demystifier]

42 fundamental questions
https://arxiv.org/abs/1804.08730v1

 

[Vanadium 50]

t what space is actually made

Call it fribbitz. Then you'd need to know what fribbitz is made of. Apologies. Actually made of.

Then its turtles all the way down.

 

[BWV]

Should someone call John and check his progress? It’s been a couple of years, he should have solved one by now.

 

[pines-demon]

Wikipedia: https://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics

 

[kered rettop]

n

Call it fribbitz. Then you'd need to know what fribbitz is made of. Apologies. Actually made of.

Then its turtles all the way down.

Correction. It's turtles all the way down until you reach the end.