Unsolved Mysteries in Physics: Beyond Quantum Mechanics

[bassplayer142]

I love to ponder over interesting questions in physics that are known or not known. What i would like is a list of some undiscovered things in physics that have not been fully understood or described. I am not really looking to find a list of Quantum physics and stuff that physicists are working on right now as I would easily get confused and it is easy enough to find those questions on my own. For instance I remember my teacher said that there was something in double slit interference that was not fully understood?

thanks

 

[Mk]

You can try this for starters :)

http://en.wikipedia.org/wiki/Unsolved_problems_in_physics

 

[polar]

I don't know where the line between "fully understood" and "undiscovered" is drawn. Gyroscopic precession, for example, may be fully described mathematically, and yet I don't recall ever learning what mechanism or property causes it.

Is it enough to just quantify something? Does that accurately define the observed phenomenon? Is this a philosophical question?

 

[Loren Booda]

Great link, Mk!

 

[arunma]

I love to ponder over interesting questions in physics that are known or not known. What i would like is a list of some undiscovered things in physics that have not been fully understood or described. I am not really looking to find a list of Quantum physics and stuff that physicists are working on right now as I would easily get confused and it is easy enough to find those questions on my own. For instance I remember my teacher said that there was something in double slit interference that was not fully understood?

thanks

Your teacher was likely talking about the fact that the double slit interference pattern can be observed when electrons are passed through the slits instead of photons, except when the electrons are observed as they enter the slits. Actually, this phenomenon is understood quite well. It doesn't make much sense to physics students, since some ideas in quantum mechanics seem highly counterintuitive. But quantum mechanics provides a framework in which physicists can understand this very well.

To answer your questions, here's a list of unanswered questions in physics that I can think of off hand:

• The question of neutrino oscillation: do neutrinos change lepton flavor?
  
• The very large temperature gradient between the Sun's corona and photosphere. The Sun's corona is one million kelvins, whereas the photosphere is about 6,000 kelvins.
  
• Observational cosmology. General relativity and theoretical cosmology have made some rather spectacular predictions about the origins and nature of the universe, and physicists are currently collecting and analyzing data that may confirm these predictions.
  
• The search for the Higgs Boson. This particle may be responsible for giving matter the property of mass.
  
• The search for dark matter, whose existence would explain why certain observed astrophysical phenomena deviate from theoretical predictions.
  
• String theory: needs no introduction.

Anyway, these are just some unanswered questions that I could recall at the moment. There are certainly many more reasons why physicists will continue to find gainful employment in the future.

 

[Ki Man]

• String theory: needs no introduction.

There are certainly many more reasons why physicists will continue to find gainful employment in the future.

String theory has run into dead ends. I don't know if it's still worth anything.

for a sec, i thought you said 'physicists will continue to find unemployment

 

[arunma]

String theory has run into dead ends. I don't know if it's still worth anything.

String theory has a good deal of potential, and by no means has it run into dead ends (at least not yet). The theory is logically consistent. All that is necessary now is for string theory to make predictions that can be tested. It's entirely possible that physicists may even have meaningful results in the next few years.

 

[Ki Man]

All that is necessary now is for string theory to make predictions that can be tested.

and when will that be?

 

[Pythagorean]

I don't know where the line between "fully understood" and "undiscovered" is drawn. Gyroscopic precession, for example, may be fully described mathematically, and yet I don't recall ever learning what mechanism or property causes it.

Is it enough to just quantify something? Does that accurately define the observed phenomenon? Is this a philosophical question?

I would think a theoretical model (the creative part) is somewhat helpful to fit the mathematical formalism, but on the other hand, a lot of science is very statistical, and models (interpretations) could only be formed later and might still be in debate.

Remember that one part of science is just being able to make predictions (the other part being satisfying curiosity). If you're a 19th century imperial general you don't care whether the scientists know why aiming the cannon at this height makes it go that far, you're just glad that they could predict it so you could hit your enemies.