Physics

[Alan Rupp]

Calling FeynmanWannabe: This is the official thread in which you explain to me quantum gravity in layman's terms.

(All others fully understanding quantum gravity on a mathematical or physical level may also jump in, note: I know nothing of differential geometry.)

[aminorthreat55]

I really wish I could participate in this discussion because I find it fascinating.

Too bad I suck ass at physics.

[Alan Rupp]

Thanks for the bump, Peter.

[itsjustadrian]

I'm taking AP Physics and I have no absolute idea what you're talking about except for the fact that gravity is 9.8 m/s2.

[ghostyouare]

I'm taking AP Physics and I have no absolute idea what you're talking about except for the fact that gravity is 9.8 m/s2.
You live in Rancho? Awesome. I think you're the closest member to me.

[Brandn3w]

i was going to take physics next year but i decided to take ecology/geology because of field trips like woah!

[Alan Rupp]

I'm taking AP Physics and I have no absolute idea what you're talking about except for the fact that gravity is 9.8 m/s2.
Get out of here EURO

32 ft/s^2

[ghostyouare]

Get out of here EURO

32 ft/s^2
hahaha

[mps]

Gravitons.

[mps]

I don't know any of the mathematics of it though...

[FeynmanWannabe]

I don't know any of the mathematics of it though...
Haha I don't really know much at all. There are more than a handful of theories, some more popular than others, but no definites by any stretch. I really hope to just learn a little this summer.

I have to get some studying done for my (physics) exam, but I hope this thread gets bumped every once in a while. :)

[mps]

Haha I don't really know much at all. There are more than a handful of theories, some more popular than others, but no definites by any stretch. I really hope to just learn a little this summer.

I have to get some studying done for my (physics) exam, but I hope this thread gets bumped every once in a while. :)

I have my exams in a week's time. I finish school for good on Wednesday, so I'm pretty happy about that. I have 3 papers for my physics exam, the first two on basically everything from mechanics, to thermal physics, electromagnetism, nuclear physics, etc etc..the pretty standard stuff. Then the third is a more specialised paper with a section on Optics and a section on Astrophysics. I wanted our teacher to teach Relativity instead of Optics but she said it was too confusing for her to teach, haha.

[FeynmanWannabe]

I have my exams in a week's time. I finish school for good on Wednesday, so I'm pretty happy about that. I have 3 papers for my physics exam, the first two on basically everything from mechanics, to thermal physics, electromagnetism, nuclear physics, etc etc..the pretty standard stuff. Then the third is a more specialised paper with a section on Optics and a section on Astrophysics. I wanted our teacher to teach Relativity instead of Optics but she said it was too confusing for her to teach, haha. I think your physics education is probably light years (no pun intended - okay maybe it was) than what I had, especially in high school.

[mps]

I think your physics education is probably light years (no pun intended - okay maybe it was) than what I had, especially in high school.

Well I am taking higher level physics. I was surprised when we went into hadrons, leptons, bayrons, etc. Apart from astrophysics, particle physics is my favourite part of physics. How much detail did you go into in your high school physics classes then?

[FeynmanWannabe]

Well I am taking higher level physics. I was surprised when we went into hadrons, leptons, bayrons, etc. Apart from astrophysics, particle physics is my favourite part of physics. How much detail did you go into in your high school physics classes then?
From what I recall it was mostly excruciatingly slow Newtonian mechanics, the most basic of optics, and pretty much everything else that you could teach to someone in middle school. It was algebra rather than calculus based...essentially, it was a joke.

[mps]

From what I recall it was mostly excruciatingly slow Newtonian mechanics, the most basic of optics, and pretty much everything else that you could teach to someone in middle school. It was algebra rather than calculus based...essentially, it was a joke.

I take higher level maths, which isn't that much fun to be honest. We do lots of calculus...:(

[FeynmanWannabe]

I take higher level maths, which isn't that much fun to be honest. We do lots of calculus...:(
Calculus was probably the biggest reason I went into physics and the thoughts of "Um, there just has to much more to physics than what was mentioned in class - I wonder what that is." My physics class was a joke. Have you taken more than one class, or how does it work?

[mps]

Calculus was probably the biggest reason I went into physics and the thoughts of "Um, there just has to much more to physics than what was mentioned in class - I wonder what that is." My physics class was a joke. Have you taken more than one class, or how does it work?

Calculus isn't that bad unless it involves intergrating things with sin and cos in... What do you mean about my classes? Like what classes I take?

[FeynmanWannabe]

Calculus isn't that bad unless it involves intergrating things with sin and cos in... What do you mean about my classes? Like what classes I take?
Yeah. All I had was my shit-tastic year-length course on "How to be bored." How much physics have you taken in HS?

[mps]

Yeah. All I had was my shit-tastic year-length course on "How to be bored." How much physics have you taken in HS?

Well I started taking physics in 9th grade, then I went into a 2 year course in 10th and 11th grade. Then for the last two years I have been doing the IB (International Baccalaureate)...they have it in the states some places, but basically you take 6 subjects in total, 3 at standard level, 3 at higher level. So I took physics, chemistry and math at higher level. That means I've done physics for a total of 5 years now, and I'm going on to do it at university (physics with astrophysics). :bigsmile:

[FeynmanWannabe]

Well I started taking physics in 9th grade, then I went into a 2 year course in 10th and 11th grade. Then for the last two years I have been doing the IB (International Baccalaureate)...they have it in the states some places, but basically you take 6 subjects in total, 3 at standard level, 3 at higher level. So I took physics, chemistry and math at higher level. That means I've done physics for a total of 5 years now, and I'm going on to do it at university (physics with astrophysics). :bigsmile:
Holy crap what a huge difference. I'm insanely jealous. No wonder they tell us that American students suck. Ugh, godammit. You just depressed the hell out of me, man.

[mps]

Holy crap what a huge difference. I'm insanely jealous. No wonder they tell us that American students suck. Ugh, godammit. You just depressed the hell out of me, man.

Hahaha, I try to read a lot of science magazines too. My teacher sometimes lends me books and stuff to help my knowledge. I just read one on predictions of what could happen in the last 3 minutes of the universe.

[FeynmanWannabe]

Hahaha, I try to read a lot of science magazines too. My teacher sometimes lends me books and stuff to help my knowledge. I just read one on predictions of what could happen in the last 3 minutes of the universe.
Lucky you. Alright, well if I'm ever going to catch up to you then I should probably get to studying. Take care man.

[mps]

Lucky you. Alright, well if I'm ever going to catch up to you then I should probably get to studying. Take care man.

Haha, good luck on that. You too.

[Alan Rupp]

Gravitons.
I don't know, graviton's have a lot of problems from what I remember.

Hahaha, I try to read a lot of science magazines too. My teacher sometimes lends me books and stuff to help my knowledge. I just read one on predictions of what could happen in the last 3 minutes of the universe.
About a year ago, we had a thread about that, but Tony (Tanooki Suit) and I (venus/bacchus) aren't the most well-versed in the topic. Check it out and fill in some gaps please.

http://www.absolutepunk.net/showthread.php?t=51402

[Alan Rupp]

Holy crap what a huge difference. I'm insanely jealous. No wonder they tell us that American students suck. Ugh, godammit. You just depressed the hell out of me, man.
Yeah, same here. I took ONE year of physics in high school, and we barely got past Newtonian mechanics. It was basically just a statics course.

And still, most of the kids were like "you're going tooo fasssst! We don't understaaaand!"

America.

[richter915]

Yeah, same here. I took ONE year of physics in high school, and we barely got past Newtonian mechanics. It was basically just a statics course.

And still, most of the kids were like "you're going tooo fasssst! We don't understaaaand!"

America.
ugh do not even start. Sometimes I feel bad cause I can't really do the calc based physics here. As a pre-med student it's best for me to stick to the life sciences major so I took non-calc based physics in college (I'm still taking it)...we really don't go into much to be honest. Some of it gets confusing...for example, our professor never full explained the importance of vectors and just kinda expected us to know it...it messed a lot of people up...he never explained the distinction between dot product and cross product so when we did stuff with electricity and magnetism...people were just confused. I'm not the type to just memorize equations, I need to understand it but he can't because it's non-calc.

the best thing though...once in my recitation...we were working on something...and the teacher was like "well we can do this 2 ways, one easily with a simple first order derivative or the long way with energy"...he starts going forward with the calculus and this stupid bitch in the class goes "excuse me, this is a non-calculus course so we don't know how to do this"...he was annoyed but said fine and did it the long way...then another question came up and he was continuing it using energy and another girl raises her hand and says we were taught to do that concept with calculus...then the teacher was like "well sorry...cause this girl (points right at her)...can't do simple calculus so we're stuck with this"

[FeynmanWannabe]

Hahaha That's awful, but I'm sure he was frustrated.

[richter915]

Hahaha That's awful, but I'm sure he was frustrated.
this guy is a nuclear physicist from somewhere in the mideast (go figure)...but he's crazy smart and I have tons of respect for him...and I felt horrible that he had to waste his time bothering with people like that. He shouldn't be allowed near a 100 level physics course and he's stuck with the worst of the worst. It's girls like her that give pre-meds a bad rep. I think I might try and teach myself some calc based physics outside of class.

[FeynmanWannabe]

this guy is a nuclear physicist from somewhere in the mideast (go figure)...but he's crazy smart and I have tons of respect for him...and I felt horrible that he had to waste his time bothering with people like that. He shouldn't be allowed near a 100 level physics course and he's stuck with the worst of the worst. It's girls like her that give pre-meds a bad rep. I think I might try and teach myself some calc based physics outside of class.
No offense, but there are a lot of students who give pre-meds a bad rep. I'm a little because those pre-meds, the ones who figued a 100 level physics couse would be a piece of cake and lashed out at the profesor when it wasn't, managed so that he didn't get tenure (mainly due to the bad student reviews, also he was't on a huge publishing spee but rather had his hand in many different projects) and left the following year. Sorry, I'm still mad. I'm sure most pre-meds aren't like that, though. I know you, at least, aren't. :)

[Alan Rupp]

ugh do not even start. Sometimes I feel bad cause I can't really do the calc based physics here. As a pre-med student it's best for me to stick to the life sciences major so I took non-calc based physics in college (I'm still taking it)...we really don't go into much to be honest. Some of it gets confusing...for example, our professor never full explained the importance of vectors and just kinda expected us to know it...it messed a lot of people up...he never explained the distinction between dot product and cross product so when we did stuff with electricity and magnetism...people were just confused. I'm not the type to just memorize equations, I need to understand it but he can't because it's non-calc.

the best thing though...once in my recitation...we were working on something...and the teacher was like "well we can do this 2 ways, one easily with a simple first order derivative or the long way with energy"...he starts going forward with the calculus and this stupid bitch in the class goes "excuse me, this is a non-calculus course so we don't know how to do this"...he was annoyed but said fine and did it the long way...then another question came up and he was continuing it using energy and another girl raises her hand and says we were taught to do that concept with calculus...then the teacher was like "well sorry...cause this girl (points right at her)...can't do simple calculus so we're stuck with this"
Lower level calc-based physics is really simple. It probably wouldn't be too difficult teaching yourself. I mean, it's really just basic integration (maybe double or triple integration or something, but that's still not complicated) and derivatives. It's gets a little trickier when you get into differential geometry and differential equations, but you're a smart dude, I'm sure you'd pick it up. That stuff isn't in any of the lower classes anyway (i.e. the ones pre-meds would take).

P.S. Pre-meds have nothing on pharmacy students.

[richter915]

No offense, but there are a lot of students who give pre-meds a bad rep. I'm a little because those pre-meds, the ones who figued a 100 level physics couse would be a piece of cake and lashed out at the profesor when it wasn't, managed so that he didn't get tenure (mainly due to the bad student reviews, also he was't on a huge publishing spee but rather had his hand in many different projects) and left the following year. Sorry, I'm still mad. I'm sure most pre-meds aren't like that, though. I know you, at least, aren't. :)
heh ya I hear you. Our main professor...the one who writes the exam...he knows exactly who is in the class and why...so he doesn't go beyond the expectations of the class...he teaches us what we have to know for the MCAT and that's it. This guy will never get fired...ever.

I've been here two years and I don't really know any truly smart pre-meds...I guess the smart ones are the ones who are orgo TAs but major in physics or comp sci...i know of a couple.

[mps]

Bump!

[Nick Lopez]

THis class is responsible for my first and only C. I got an A + this semester, though.

[blackandblueNFG]

me am physics major

[surreality]

No offense, but there are a lot of students who give pre-meds a bad rep. I'm a little because those pre-meds, the ones who figued a 100 level physics couse would be a piece of cake and lashed out at the profesor when it wasn't, managed so that he didn't get tenure (mainly due to the bad student reviews, also he was't on a huge publishing spee but rather had his hand in many different projects) and left the following year. Sorry, I'm still mad. I'm sure most pre-meds aren't like that, though. I know you, at least, aren't. :)

Hahaha, sounds awful. I was thinking of switching to Pre-Med since I whooped them in Physics and Math this past year. ART PRIDE :)

[Bean]

Damn, insightful stuff. mps, you've been taking physics classes since the ninth grade...and I'm just taking my first physics class next year (senior in high school). "Americans" is fucking right. I hate the stupid bitches in my science classes, but I'm a guilty slacker, too. It's people like you guys that make me wish I wouldn't have started lazying about...whenever I started. Typical American redneckville slouch I am.

But, anywho...particle physics is also my favorite part about physics, even though all the "research" I do is purely on my own time out of interest. I noticed mention of pre-med and pharmaceutical courses, and it's possible that I'll be pursuing one or the other.

This thread just reminds me of how much I don't have my life in order.

/rant
/bump

Edit: Haha...just realized how old this thread was. I'm a newb, shoot me. Maybe the discussion will continue.

[richter915]

From what I recall it was mostly excruciatingly slow Newtonian mechanics, the most basic of optics, and pretty much everything else that you could teach to someone in middle school. It was algebra rather than calculus based...essentially, it was a joke.
good ol regents level physics...man I took the regents after they dumbed it down...and I barely managed a 92...it's weird, they made it easier to pass but harder to get 100 on.

[BryterJonah]

riW0wQd5z2M

Physics is how I'm spending a majority of my Summer. Downloaded texts and seen a multitude of videos on various related topics and theories. What sucks is now I'm torn between whether I'd want to major in English or this.

Thank god I'm my age.

[Kid B]

Good bump

[nlo13]

physics is awesome.

[Schmidty Says]

I hate physics. Chemistry all the way!

[nlo13]

Ha. I was always way better at physics than I was at Chemistry

[NickLopez]

THis class is responsible for my first and only C. I got an A + this semester, though.
What a punk, talking like I was one of the group.

[OnLettingGo]

Yeah, same here. I took ONE year of physics in high school, and we barely got past Newtonian mechanics. It was basically just a statics course.

And still, most of the kids were like "you're going tooo fasssst! We don't understaaaand!"

America.

this happened almost every year in AP physics so our school turned it into a block course along with AP chemistry. And still almost everyone failed. I thought it was relatively easy and got an A. Also took Calculus along with it. Hated the back and forth between 9.8m/s^2 and 32ft/s^2.

[FeynmanWannabe]

I still approve of this thread. :thumbup:

[mps]

Me too, complete with my newly aqquired degree :)

[JuneJuly]

taking it this year, as a senior. needed a science credit. at my school, it's basically a joke.

[BryterJonah]

It's basically a joke.
Up yours

[JuneJuly]

Up yours

I bet yours is a lot harder than mine (no homo)

[reachforthesun]

physics is great. i majored in it in college. amazing stuff. and, a respectable degree that can land you in engineering, teaching, consulting, etc.

my favorite, however least relate-able subject in physics, was relativity. crazy stuff

[John JD Dorian]

physics is great. i majored in it in college. amazing stuff. and, a respectable degree that can land you in engineering, teaching, consulting, etc.

my favorite, however least relate-able subject in physics, was relativity. crazy stuff

relativity is sick.

especially how it fits in to quantum mechanics and electromagnetism.

[reachforthesun]

relativity is sick.

especially how it fits in to quantum mechanics and electromagnetism.


it's definitely an 'ah-ha' moment when your mind is ready to understand how it all relates. people always told me quantum would be hard mathematically, but i found it to be harder to comprehend than anything else.

[John JD Dorian]

it's definitely an 'ah-ha' moment when your mind is ready to understand how it all relates. people always told me quantum would be hard mathematically, but i found it to be harder to comprehend than anything else.

it's not so much that it's hard mathematically, but in newtonian mechanics you generally have your intuition to guide you with the math, so it doesn't seem as daunting. you can plug through the calculations and then if you get an answer that makes physical sense to you, you feel good about it.

in E&M and in QM you really don't have any experience or intuition, so you have to rely more on the math to guide you through.

[reachforthesun]

it's not so much that it's hard mathematically, but in newtonian mechanics you generally have your intuition to guide you with the math, so it doesn't seem as daunting. you can plug through the calculations and then if you get an answer that makes physical sense to you, you feel good about it.

in E&M and in QM you really don't have any experience or intuition, so you have to rely more on the math to guide you through.


i think the worst part of QM is knowing that you will never, ever use it in real life. unless you go to CERN or something like that.

[John JD Dorian]

i think the worst part of QM is knowing that you will never, ever use it in real life. unless you go to CERN or something like that.

but it's so mindblowingly cool that it's worth knowing.

it's beautifully philosophical, too. the ideas of QM lend a lot to the ideas of existentialism and free will.

[reachforthesun]

but it's so mindblowingly cool that it's worth knowing.

it's beautifully philosophical, too. the ideas of QM lend a lot to the ideas of existentialism and free will.


my senior research project was on the Many Worlds therom. have you checked that out?

[John JD Dorian]

my senior research project was on the Many Worlds therom. have you checked that out?

nope.

[reachforthesun]

its pretty cool - schrodingers cat, etc.

[FeynmanWannabe]

<3 Physics, although it kicks my ass on a daily basis.

[Alou]

Hated that class. The teacher did everything for us so I passed with a 109. (AP) Didn't learn shit though.

[$eth]

Started AP Physics today at my high school. I'm a little worried since I'm only taking pre-calculus this year. The class seems like it'll be really fun though.

[Supernovacaine]

Calling FeynmanWannabe: This is the official thread in which you explain to me quantum gravity in layman's terms.

(All others fully understanding quantum gravity on a mathematical or physical level may also jump in, note: I know nothing of differential geometry.)


Differential geometry is a huge pain in the rear. Its the underlying mathematics (that, tensor geometry and quantum field theory) that try its best to simplify and make sense of quantum gravity. It doesn't help that its very challenging to follow (I took a differential geometry and a QFT course in my final year of undergraduate physics and math). Currently there really isn't exactly an efficient model of quantum gravity; it depends if gravitons and the Higgs Boson actually exist. Quantum gravity (in my best layman's terms) is the suggestion that interacting gravitons (a massless particle, in theory) can cause the curvature of spacetime and somehow produce a force of gravity. This is being worked on through means of string theory, which is basically the idea that instead of little particles floating around in space, they are instead a 2-D string vibrating inside a 1-D membrane, and all of this hoopla is going on in 11-D spacetime. String theory essentially predicts the presence of gravitons, but this has yet to be proven to exist.

[vodyanoj]

Calling FeynmanWannabe: This is the official thread in which you explain to me quantum gravity in layman's terms.

(All others fully understanding quantum gravity on a mathematical or physical level may also jump in, note: I know nothing of differential geometry.)

No such thing as quantum gravity in layman's terms: the terms do not exist. But I can recommend some books that would come close and give you a good payoff with some effort. For popular treatments, look at Lawrence Krauss "Quintessence", Lisa Randall's "Warped Passages" and Leonard Susskind's "The Cosmic Landscape". All are pretty much math-free, so you don't have to worry too much. But you can only go so far that way. If you want to understand it (or, at least, undertand it as well as humanity does at the moment), you cannot avoid 3 semesters of calculus, 1 of DE's and 1 of linear algebra, at the very least. And while you are at it, you can keep yourself entertained with books like Gasperini's "The Universe Before the Big Bang", and, of course, the 3-volume set of aforementioned Feynman, even though it si a bit dated. For an up-to-date overview, you'll ahve to work your way through standard QM on the upper-division level, a graduate course in QFT and another one in GR. Nice overviews are in Weinberg, "Quantum Theory of Fields" (3 vols)...:)

You get the picture. Also, if you are hip on modern philosophy and its interaction with physics, you can jump straight off the deep end into "Physics Meets Philosophy on the Grand Scale: Contemporary Theories of Quantum Gravity".

All are available on amazon, and all are better writers than I am...Good luck.

[vodyanoj]

but it's so mindblowingly cool that it's worth knowing.

it's beautifully philosophical, too. the ideas of QM lend a lot to the ideas of existentialism and free will.

QM =/= free will. Randomness and probabilistic outcomes are not freedom.

[The Personist]

QM =/= free will. Randomness and probabilistic outcomes are not freedom.

Do you believe in free will?

[vodyanoj]

Do you believe in free will?

Depends on the scale of observation. It appears to us, as agents in the macroscopic Univers,e that we have free will. But there is no ontological reality to it: it is only an artifact of scale. Deep down we all are made of the same particles, interacting in the same way as those of rocks, lizards, stars, echinoderms, vaginas and meteorites do. The interactions are so complex that I may even agree that we shall never be able to solve them on the fundamental level, so we shall always have the appearance of free will, but not the reality of it.

[tommyishere]

im in regular physics, and its easy