Physics is actually a good degree. How often do you get to spend 3-4 years on something that doesn't have to do with your career?

However, as good as physics is, I seriously think that the passion for physics changes when one comes into contact with professors.

A bad mix of professors whom most are pricks can really pull down your morale. But then again, there are those exceptional few who really ask probing questions that would make you start thinking. I have to say I thoroughly enjoyed the classical mechanics class and its treatment on gravity, why is the law of gravitation 1/r^2 and not some random number and despite the advances in particle physics no one really understands what is gravity.

Why is the Lagrangian and the Hamiltonian so simple yet so powerful in solving problems? Why weren't we thought these tools when when we were younger? Felt stupid and led around by trying to solve problems using forces......................

form 4 this year, very green to this thing called physics.. anyhow, this linear motion thing interest me a lot,

i got a question, is taking physics as a major hard? Coz i want to take it, but then theres this few devilled-fren of mine implenting that physic is so dam hard

At the degree level,physics (pure science) is probably more difficult to understand than engineering (applied science) because it involves a lot of theories. To know whether you have the passion, I would suggest you go through SPM and A-level/STPM (as a gauge). If you have the passion for it, go for it.

is engineering a little connected to physics?

You'll need to use theories and formulas from physics in many aspects/fields of engineering.

Physics was by far my fav subject in high school. I haven't read much about physics for the past few yrs since my career is in IT now.

I love Physics because I enjoy learning how things work, and it is not a subject that requires heavy memorization.

My fav subtopic in Physics is electromagnetic radiation.
My most hated subtopic is Optics (not interested at all).
The subtopic I find most difficult to understand is Electricity (dunno why, it's my weak point)

This post has been edited by socratesman: Jun 15 2009, 07:59 PM

I've been doing some laymen studying on quantum mechanics, general/special relativity, string theory and some cosmology (dark matter, planet/star/nebula/galaxy, how everything came to become everything). Mostly just documentaries and wikipedia.

It is most interesting. I dont really like the math tho, or math in general I wonder if I can go back to school for it (without the math involved hopefully) for it.

too bad it wasnt covered while i was in high school and it was way different cos it was in bm.

Yes,it's more like applying the laws of physics to solve problems.

Perhaps the mathematics involved in Lagragian&Hamiltonian is a bit difficult for secondary school level.
But to be honest, partial differential and other differential equation should be taught at pre-u level.
Well, nowadays if you go through the content of matrikulasi/stpm/a-level... well..

Do you still do physics? Can i know what's your research area?

certainly yes. To be more precise, engineering is a combination of applied physics, chemistry, mathematics, biology etc. Sounds more towards chemical engineering though. lol

Optics can be very interesting at higher level. (no more snell's law etc, lol)
Electricity and magnetism can be difficult at first, but it is essential at any research field of physics. You just have to force yourself go through it.

Wikipedia and documentaries study won't help much in *real* understanding of the physics.

You will certainly need mathematics no matter what cause it is basically the soul of the physics.

QM needs mathematics of undergrad level. Perhaps more difficult in solving some special function.
GR is WORSE. Basically i can say that no one knows about GR in Malaysia. Tensor itself is already a killer.
String theory also same like GR while cosmology is a little bit too general to discuss about its mathematics.

You can do physics by youself but you can't escape from the mathematics.
There are examples in US where they study physics by self study while working as well. They are able to publish paper or proposed some new ideas as well.

Don't give up if you really love physics.

oh sorry i didn't answer your question. I am currently studying the energy distribution, polarization and other properties of specific thin film.

I am still not having any paper yet because i just started my research few months ago.

you?

I am just an engineer in the telco industry but science is my past time, and I know how watered down the science I get from reading wiki, and all those internet sources.
I guess I can google the stuff you mention and throw some questions.

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Added on June 16, 2009, 2:51 amAre you telling us classic mechanics like the Newton Laws are not up to snuff? Care to elaborate?
Those classical formulas have classical calculus proof already.

This post has been edited by beatlesalbum: Jun 16 2009, 02:51 AM

beatlesalbum: There exists an alternative reformulation of classical mechanics in a variational setting, and this is what we call Lagrangian/Hamiltonian mechanics, and they're very useful, and beautiful refomulation, because of the following reasons:

1) The form of the formulas is independent of the coordinate system, i.e. take Newton's laws, and apply it to a cylindrical coordinate/spherical polar coordinate system. You'll find out that the equations change when you change the coordinates. These don't.

2) It incorporates in symmetries very well (Noether's Theorem), and conservation laws are incorporated into the Lagrangian/Hamiltonian. e.g. if the Lagrangian is independent of some coordinate, then you get a corresponding conservation law, or symmetry.

They're widely used in quantum mechanics, where the Hamiltonian is the governing equation, and in quantum field theory, where the Lagrangian is employed heavily.

edit: and no, wiki can be very detailed too, it's just that the maths without an introduction would probably confuse most people.

edit: to add, Lagrange's formulation in the Lagrangian involves a minimisation problem of minimising some quantity called the action. Just think of it as a more complicated version of taking some curve, and using dy/dx to find the minimum of that curve - it's something like that, and Lagrange's formulation allows you to take all the classical mechanics problems we're used to seeing, and then solving for the 'true' trajectory (the trajectory that is actually taken by the particle) by finding the trajectory that minimises this action quantity.

This interpretation (Lagrange's) doesn't really work in quantum mechanics, because we're considering the probabalistic nature of quantum physics. It was a Richard Feynman, which is probably feynman's namesake, that formulated the quantum mechanical equivalent of Lagrangian classical mechanics, or the action principle to something called the path integral formulation, where the particle goes through all possible intermediate states between some initial state A and final state B, weighted by the probability of each intermediate state. feynman's avatar can then be seen as one of the possible paths for some particle interaction [actually to be more precise, it's a 2nd order diagram describing an annihilation and pair production of a particle and a antiparticle], and his avatar is called a Feynman diagram after the man that invented it himself. These Feynman diagrams are used a lot by particle physicists.

I've probably said too much now, but yeah it should give you an idea of what it is, and perhaps I might've also explained feynman's nickname and his avatar

probably final edit: What exactly is the classical calculus proof of Newton's Laws? I think they're taken to be axioms instead.

This post has been edited by bgeh: Jun 16 2009, 06:57 AM

ModularHelmet: personally I prefer that specific discussions go into their own threads, but chat and one-off questions can remain in an "umbrella cover-it-all topic" like this one. Please help me watch this thread, thanks

dont worry. i will take care of this thread.

a general talk on physics is always good as it will give some new insight to people who don't know before this. Hope this will go on well.

So,i guess Eulerian approach is only used commonly in fluids.Does Eulerian approach used in other field of physics?

Just a curiousity.

This post has been edited by Cheesenium: Jun 16 2009, 06:10 PM

No the Eulerian and the Lagrangian approach in fluid dynamics (they're essentially points of view, one an outside observer, the other, an observer following a single fluid particle) is very different from the Lagrangian (a quantity that you have to compute) in mechanics

Isn't optics a subtopic of EM radiation albeit a specialized part

This post has been edited by befitozi: Jun 17 2009, 07:51 PM

Lol just wanna where can I start in increasing my knowledge on physics? I forgot most of the stuff taught in secondary school already.

I know, besides going back to the secondary school textbooks, where else can I start?

Depends on how strong is your basics.

A good physics book which i enjoyed reading is the "Feynman Lectures". Maybe you can start there though if you say you forgot most of secondary level physics, it may be tough.