The Importance of Theoretical Physics

[RuroumiKenshin]

What is the importance of theoretical physics to our modern society?
People often inquire, when I inform them that I wish to get a PhD in it, what the importance of it is. What is the point of theoretical physics? I guess it is the framework open which microchips are built! That is, quantum mechanics is involved, right? Okay, so I'm clueless here...

 

[kyle_soule]

Theoretical physics is always pushing the envelope, and also creating/discovering the physics of tomorrow. There is no need for putting all your man power on the now, when the future will be at hand soon. This, in fact, would leave you at a stand still when you passed from the now ( into the 'later' ) for a while in order to push ahead again, you would find yourself with nothing to work on as others, ultimately, worked on theoretical physics.

Basically, they create the theories to be tested when the equipment is available. Much like designing cars of the future, they have no real importance now, but they will be in 10+ years.

 

[damgo]

Well, it depends on the field of physics. Theoretical work in, say, plasma physics or condensed matter physics has great promise in developing nifty new things like superconductors, fusion reactors, amazing new materials, and so on. Theoretical work in high-energy physics or cosmology -- like most of the stuff in this forum -- well, it's hard to imagine how that could ever be really "useful." I do it because 1) I enjoy it, and 2) I think understating the fundamental workings of the universe is important for its own sake.

 

[wimms]

Importance to society, in this order:
- new weapons. (sorry, this is still usually first on the list)
- communication and observation (incl big brother)
- energy
- travel
- computing
..
..
- fate of universe, and perhaps meaning

 

[quantumdude]

Originally posted by MajinVegeta
What is the importance of theoretical physics to our modern society?

Queen Victoria asked that question of Michael Faraday when he demonstrated this "useless" phenomenon called electricity to her. She asked "Of what use is it?" and he replied, "Of what use is a newborn babe?"

 

[Locutus]

The theory of relativity is still considered by many to be theoretical physics. From SR we have E=mc^2. From E=mc^2 we have nuclear weapons and energy.

GPS systems factor in effects of relativity when they operate, or else they would be innaccurate.

For relativity alone there are many other examples of how it has affected our world. And relativity is just one theory that falls under the domain of nonclassical, "theoretical" physics.

 

[FZ+]

I have always thought that the search for knowledge is an end in itself. The practical applications are just fortunate side-effects.

 

[quantumdude]

"Physics is like sex. Sure, it may give some practical results, but that's not why we do it." - R. Feynman

 

[selfAdjoint]

"Pour l'honneur de l'esprit humaine". who said that? Laplace, Lagrange?

 

[damgo]

lol... I heard the electricity anecdote a little differently. When Gladstone was British PM, he visited Faraday's laboratory and asked if some esoteric substance called `Electricity' would ever have practical significance. Faraday responded "One day, sir, you will tax it."

I suspect it might be an urban legend, but it's still funny.

 

[climbhi]

Originally posted by Tom
"Physics is like sex. Sure, it may give some practical results, but that's not why we do it." - R. Feynman

I love that quote. Too people who talk to me about being a physics major and what type of physics I like to study and then ask me of what use it is I've gotten into the habit of replying "absolutely no use at all, just beautiful." But then usually add some stuff to the end of it like "Of what use was going to the moon? What was the use for Columbus going back to America after he failed to find a better trade route to India. And even worse yet of what use was going back to the moon after we'd already been there? Sometimes useless things are important you see..."

 

[Ivan Seeking]

Q: "What is the importance of theoretical physics to our modern society?"

A: We won't know until we're done.

Here are some of the hopes I have heard expressed: To know the mind of God; to attain a complete understanding and the eventual mastery of nature; to make really cool flying cars; to build warp-field laser blasters? You tell me; how much is possible?

"It is very important that we do not all follow the same
fashion... It's necessary to increase the amount of
variety... and the only way to do this is to implore you
few guys to take a risk with your lives that you will not
be heard of again, and go off into the wild blue yonder to
see if you can figure it out." Richard Feynman(1965),

Nobel prize in physics award address.

 

[plus]

Originally posted by Tom
"Physics is like sex. Sure, it may give some practical results, but that's not why we do it." - R. Feynman

Practical results are what brings in the money for physics, but not for sex

 

[quantumdude]

Originally posted by plus
Practical results are what brings in the money for physics, but not for sex

Are you calling me a prostitute?

 

[plus]

Originally posted by Tom
Are you calling me a prostitute?

No, although I was alluding to the field. Are you?

Theoretical physics is the glamorous part of physics, and it makes so much less money than its ugly applied side. Why is this?

 

[Ivan Seeking]

Hello MajinVegeta,
What is the importance of theoretical physics to you? Why do you want a PhD? I am suprised to hear of such interest in a subject for which you know of no purpose.

 

[Mike H]

As for why theoretical physics rakes in less money than the applied side...see again damgo's comment. If you're a theoretical physicist whose specialty is biophysics, you can probably find a way to get people to fund your research and pay you to go figure out some things about protein folding, cellular dynamics & transport, model genetic expression and regulation of interesting processes, try to provide some idea of actual neural networks, or other such sundry things.

I would also be careful in not setting up a "theoretical" vs. "applied" divide. What do you call an experimental high energy physicist then, for example? It's not like they're interested in developing accelerator physics for medical treatments, but nor are they necessarily plugging away with their stack of math texts and papers at their side working on quantum gravity and the latest new trend in the field. Even if you were to set up a "basic" vs. "applied" divide, it's still kind of shaky. People are fundamentally interested in things like superconductors and the many body physics of them. People are also interested in superconductors due to their properties and what you could make with them. People are interested in the physics of liquids since they love stat mech. Other people are interested in the physics of liquids since if you can understand liquids, you can get some idea how to model solvents in biochemistry and medicinal chemistry.

Applied physics makes things that are directly, tangibly useful and people are willing to pay money for - that is why it rakes in the dough. If you tell someone you can make a cheaper, faster computer chip via molecular electronics and nanotech, you will get funded. If you can find a way to improve superconductors so you can do whatever someone is interested in doing, they'll support your work. There's the apocrypal story of how a scientist at a national lab, when asked by Congress about the value of the research they did there in high energy physics, replied : "It has nothing to do with national defense except to make our nation worth defending."

 

[quantumdude]

Originally posted by Mike H
I would also be careful in not setting up a "theoretical" vs. "applied" divide.

Yes, I always regarded it as "theoretical" vs. "experimental". If you're in a lab, you're experimenting. If you're solving equations, you're theorizing.

 

[climbhi]

Originally posted by Tom
Yes, I always regarded it as "theoretical" vs. "experimental". If you're in a lab, you're experimenting. If you're solving equations, you're theorizing.

Sorry to get so far off topic with this but one of the things that bothers me is it always appears that when you get to graduate school you have to choose either to be a theorist or an experimentalist and once you've decided that's it you're a theorist who will just look at experiments for the rest of your carreer or you're an experimentalist who will get results for theorists for the rest of your carreer. Is it really unheard of to do both? I really like to tinker with things, but also like to think about how things are actually working. I guess what I'm saying is I'd like to be an experimental theorist. Can you do this, or is there simply no room for it?

 

[quantumdude]

I don't know any "experimental theorists", and the reason is that it's just so difficult to get a PhD in either one or the other that most people just want to get on with life after they are finished. However, the one guy I can think of off the top of my head who pulled it off and was great at both is Enrico Fermi.

 

[climbhi]

Well I have no problem choosing just one or the other to write my dissertation on, its just I don't want to have to be only a theorist/experimentalist (whichever one I choose to write a dissertation on) for the rest of my career. I can see nothing more enjoyable then first experimenting to find some new weirdness and then theorizing as to what is causing this new weirdness. You get the complete package and get to work with your baby the whole way through. It doesn't get any better then that. That's why math is interesting; you find something and then (hopefully) show why it is that way.

 

[Mike H]

I figured I had to add my two cents in here.

I'm doing my graduate work in biophysics in a chemistry department where I'm doing both theoretical and experimental work. (It's a long story.) The thing is, I am having to be realistic about my graduate studies because I am not going to be able to spend as much time delving into things as I'd like. I have a strict five year limit on grad school due to departmental regulations. I am not going to be able to spend as much time picking apart the intricate details of the theoretical and computational tools as I'd like, nor will I likely be able to spend as much time as I'd like to be mastering solid state NMR or the preparative wet work that will be needed. I chose a reasonably easy model system and will be working with methods that have a good bit of history to them - if I do any breakthrough work, it will much more be likely in the area of the biophysical questions I'm asking and not in the theoretical or experimental fields from which I'm drawing upon to do such work. (Not to say that it couldn't happen, of course, but am being realistic.)

My two cents for what it's worth. It probably is possible in some fields (I seem to also see strong collaborative efforts in materials physics & engineering), but probably a bit more difficult in others.

 

[plus]

Originally posted by climbhi
Well I have no problem choosing just one or the other to write my dissertation on, its just I don't want to have to be only a theorist/experimentalist (whichever one I choose to write a dissertation on) for the rest of my career. I can see nothing more enjoyable then first experimenting to find some new weirdness and then theorizing as to what is causing this new weirdness. You get the complete package and get to work with your baby the whole way through. It doesn't get any better then that. That's why math is interesting; you find something and then (hopefully) show why it is that way.

Then stay in high school for life.

Things on an indeustrial scale require a lot more specialism.

 

[Alexander]

Theoretical physics is nesessary to explain why universe and things in it are such, why they behave certain way and where they all come from.

Unfortunately nobody is interested in that (besides couple government agencies and a few journals) - exactly because theoretical physics is not making money right here and right now.

Does it sound strange that greedy investors/sponsors don't want to wait for 30-50 years for chances to increase their investment by an order-two of magnitude? That they looking for shorter-term projects (to get return before they die)?

What would you do were you in their shoes? Would you invest in each and every "blue sky" research effort?

 

[Will]

Originally posted by plus
Theoretical physics is the glamorous part of physics, and it makes so much less money than its ugly applied side. Why is this?

Because we are a materialistic society that doesn't have much value for things that can't be practically useful right away. Shameful, because it is the theoretical physics of today that makes the applied physics/engineering of tommorow. As someone studying engineering, I have the highest respect for this field. Such a large base of knowledge. To me, the theoretical side of physics and other sciences are more "pure", only seeking the truth for truths sake only, which is to be admired.

 

[Alexander]

Because it is almost impossible to survive on theoretical physics alone, many theorphysicists have to teach introductory physics courses or to do applied projects on side.

 

[RuroumiKenshin]

Originally posted by Ivan Seeking
Hello MajinVegeta,
What is the importance of theoretical physics to you? Why do you want a PhD? I am suprised to hear of such interest in a subject for which you know of no purpose.

Well, I have always looked at the universe with such great awe, and wonder. I've always had a special passion to understand space in particular. Ever since I was 6! So, I want to dedicate my life to understand as much as I can. And I don't care what people say about my getting a PhD in something THEY don't see as something profitable.
I can't answer them with what I just said and say "'cause I want to" or something. So I want to give them an answer they'll never forget, one that'll make them see a use in theo. physics.

 

[Ivan Seeking]

Originally posted by MajinVegeta
I can't answer them with what I just said and say "'cause I want to" or something. So I want to give them an answer they'll never forget, one that'll make them see a use in theo. physics.

Well, if you want to kick them in the knees a bit I would ask: Well, exactly what is possible? Then simply tell them that it is likely that we will learn something new. When physicists figure out something completely new, it usually changes the world forever. And I repeat: All of physics is justified if we can just build flying cars!

 

[RuroumiKenshin]

the common question that stumps me is "what can physics do for humanity?" and then they later insist that biology is the way to go because it actually does help humanity.

 

[Ivan Seeking]

Originally posted by MajinVegeta
the common question that stumps me is "what can physics do for humanity?" and then they later insist that biology is the way to go because it actually does help humanity.

No doubt, many new brave frontiers exist in various fields of biology - with genetic engineering clearly emerging as a favorite. And what do the biologists need to continue their work? The same as the computer, laser, pharmaceutical and medical, automotive, and energy people to name a few - Physics. One example is a recent visit that I made to SLAC. A great deal of the research is physics for other disciplines of science…and a lot of biology

Consider also what you find in hospitals these days. I used to work on CT and MRI Scanners and I'm married to a CT/MRI technologist, so I know a little about this field. We find more and more sophisticated diagnostic devices all heavily rooted in physics - FMRI, Spiral CT, Digital Angiography, Lithotripters , ultra-sound and IR imaging systems to name a few; and an entire library of nuclear medicine specialties, including PET - Positron Emission Tomography. Sound like physics? And we have an ever widening array of isotopes for better resolution and targeting. Also, there are electron and other beam therapies; one that uses latent Star Wars [SDI] laser targeting algorithms for brain and other tumor treatments. Really, you should check out the state of the art in medicine these days. Some hospitals have their own linear accelerators and they have for some time. These things mean that we can use less or non-invasive procedures and provide better diagnostics and treatment where no options or much less desirable options once existed.

Where can computers go without physicists? Who else is up to Quantum Computing…even in principle? On the other hand, if you want to live 400 years you may need to design viruses that can target specific diseases or that can modify DNA and repair genetic defects. Also, we may find that nano-technology yields many miracles. Of course, buckyballs and the child carbon nano-tubes sound promising. Have I mentioned anything not likely to require an increasingly sophisticated level of understanding of quantum physics? Additionally, we do have this little problem with an addiction to the 150 year old technology of internal combustion engines. How about a little hydrogen or fusion for power?

Many argue that physics is the root of all science. Usually we imagine the mathematical roots, the physics trunk, and then the other branches of science as a tree. This connection was almost lost until recent years, but it seems that now many disciplines must once again return to their parent subject Physics. For career options, it’s all a matter of recognizing the timely opportunities. I am quite sure that more and more will be found in years to come.

 

[Stranger]

What is the importance of theoretical physics to our modern society?

do you not agree that science (which is almost completely physics) can replace religious beliefs...

 

[Alexander]

Haven't it yet? In Europe and other places, at least. US will follow too sooner or later.

 

[RuroumiKenshin]

Originally posted by Ivan Seeking
No doubt, many new brave frontiers exist in various fields of biology - with genetic engineering clearly emerging as a favorite. And what do the biologists need to continue their work? The same as the computer, laser, pharmaceutical and medical, automotive, and energy people to name a few - Physics. One example is a recent visit that I made to SLAC. A great deal of the research is physics for other disciplines of science…and a lot of biology

Consider also what you find in hospitals these days. I used to work on CT and MRI Scanners and I'm married to a CT/MRI technologist, so I know a little about this field. We find more and more sophisticated diagnostic devices all heavily rooted in physics - FMRI, Spiral CT, Digital Angiography, Lithotripters , ultra-sound and IR imaging systems to name a few; and an entire library of nuclear medicine specialties, including PET - Positron Emission Tomography. Sound like physics? And we have an ever widening array of isotopes for better resolution and targeting. Also, there are electron and other beam therapies; one that uses latent Star Wars [SDI] laser targeting algorithms for brain and other tumor treatments. Really, you should check out the state of the art in medicine these days. Some hospitals have their own linear accelerators and they have for some time. These things mean that we can use less or non-invasive procedures and provide better diagnostics and treatment where no options or much less desirable options once existed.

Where can computers go without physicists? Who else is up to Quantum Computing…even in principle? On the other hand, if you want to live 400 years you may need to design viruses that can target specific diseases or that can modify DNA and repair genetic defects. Also, we may find that nano-technology yields many miracles. Of course, buckyballs and the child carbon nano-tubes sound promising. Have I mentioned anything not likely to require an increasingly sophisticated level of understanding of quantum physics? Additionally, we do have this little problem with an addiction to the 150 year old technology of internal combustion engines. How about a little hydrogen or fusion for power?

Many argue that physics is the root of all science. Usually we imagine the mathematical roots, the physics trunk, and then the other branches of science as a tree. This connection was almost lost until recent years, but it seems that now many disciplines must once again return to their parent subject Physics. For career options, it’s all a matter of recognizing the timely opportunities. I am quite sure that more and more will be found in years to come.

Wonderful examples, Ivan. I'm set! Really, people should consider what is the basis of discovery. Geneticists need to have computers to understand the algorythmic patterns of the DNA molecule. Engineers need physics to understand the electric currents, and stability of structures and microchips. Thanks a bunch!
One more question: How would you describe theoretical physics to someone who wants it in "english"? A lot of people ask me what it is, and well, I get stuck using "big" words that are too "scientific" for them. So does anyone have a definition that's in "English"?

 

[Ivan Seeking]

Originally posted by MajinVegeta
One more question: How would you describe theoretical physics to someone who wants it in "english"? A lot of people ask me what it is, and well, I get stuck using "big" words that are too "scientific" for them. So does anyone have a definition that's in "English"?

I see Theoretical Physics as the effort to reverse engineer reality. Or, how about the effort to describe the rules that govern how everything works? This gets difficult because all that I can think of ends with everyting, existence, reality, or, all that is. Then I want to use words like "truth" but that's not really correct. Many say Physics asks "what" not "why". But to me this becomes a matter of semantics; why does the ball fall as opposed to what causes the ball to fall...seems more like a word problem. But still, the distinction that we "model" reality as opposed to "knowing" reality I think is important...just so that people don't try to make a religion out of it.

 

[RuroumiKenshin]

lol, yeah, I have trouble with the semantics too. But I like to excuse it all by saying, 'oh, they won't catch it!'. My definition of theoretical physics is (when I'm telling someone in a conversation): "First off :physics is a science which mathematically specifies the physical prospects of the universe. Secondly, theoretical physics is what describes the theoretical aspects of physics."
the common question: "Theoretical? what's that?"

"Just things that can't ALWAYS be tested physically, but mathematically. Theoretically. Things like the quantum chromodynamics of the Big Bang, parallel universes."

Even then, I am very mad at myself, for not giving an accurate definition. What I usually say isn't the best, but its a start. Even after what I said (above), people stare at me blankly. I think I should memorize I dictionary definition:

The science of matter and energy and of interactions between the two, grouped in traditional fields such as acoustics, optics, mechanics, thermodynamics, and electromagnetism, as well as in modern extensions including atomic and nuclear physics, cryogenics, solid-state physics, particle physics, and plasma physics.

Tha above is only a definition of 'physics', but not theoretical physics. How do you describe the "theoretical" part?? that's what I'm having trouble with.

 

[Stranger]

How do you describe the "theoretical" part??

as far as I know...exclude the problem solving part...rest all is theory...

 

[Ivan Seeking]

Originally posted by MajinVegeta
lol, yeah, I have trouble with the semantics too. But I like to excuse it all by saying, 'oh, they won't catch it!'. My definition of theoretical physics is (when I'm telling someone in a conversation): "First off :physics is a science which mathematically specifies the physical prospects of the universe. Secondly, theoretical physics is what describes the theoretical aspects of physics."
the common question: "Theoretical? what's that?"

"Just things that can't ALWAYS be tested physically, but mathematically. Theoretically. Things like the quantum chromodynamics of the Big Bang, parallel universes."

Even then, I am very mad at myself, for not giving an accurate definition. What I usually say isn't the best, but its a start. Even after what I said (above), people stare at me blankly. I think I should memorize I dictionary definition:



Tha above is only a definition of 'physics', but not theoretical physics. How do you describe the "theoretical" part?? that's what I'm having trouble with.

Who is your audience? You said English. Everything I have read would still sound complicated to a non-technical person. But as far as defining theoretical, do you just need a good synonym? How about the abstract or conceptual development or modeling as opposed to testing. If you get too specific you may quickly lose people with the details.

 

[RuroumiKenshin]

My audience is usually non-technical people, who have no background in physics expcept for their high school physics class. So I should be general?
Should I just say "Physics is the study of movement"? That's very general.

 

[Alexander]

Theoretical physics = mathematical reasons of why universe is such.

 

[RuroumiKenshin]

or rather theoretical physics=mathematical theories that describe the universe. Your way of putting it, Alexander, defines m-theory.

 

[Mentat]

Originally posted by MajinVegeta
or rather theoretical physics=mathematical theories that describe the universe. Your way of putting it, Alexander, defines m-theory.

Not really, as M-Theory takes a string/brane approach to the answering of that question. He is describing a T.O.E., IMO.

The definition of "theory" is the product of rigorously testing an hypothesis. IOW, if you have an hypothesis (a testable speculation) and you test it rigorously (and it passes all of the tests), then it "graduates" to "theory".

 

[plus]

To say that theoretical physics is restricted to M theory or a TOE is wrong. Theoretical physics is physics using calculations rather than working on devices or experiments.

As such, QM is a main part ot theoretial physics, as is GR.

Any TOEs are pointless in a practical scenario, as QM and GR are correct in the situations in which they are considered.

You will find a very few theoretical physicsists working on M theory. Even in the maths departments, they are still mainly working on QM & GR.

 

[totoro]

Originally posted by MajinVegeta
My audience is usually non-technical people, who have no background in physics expcept for their high school physics class. So I should be general?
Should I just say "Physics is the study of movement"? That's very general.

if you want them to understand what theoretical physics is... i think that tell them exactly the word from the dictionary. i think they will be more clearer because dictionary is for someone who don't understand some word.