[quote]pushharder wrote:
This ^ is what I love about America.
This is not happening in Mozambique.[/quote]
Agreed!
[quote]Dr.Matt581 wrote:
[quote]squating_bear wrote:
I should probably keep my mouth shut on this (because I could be wrong), but I think I remember learning about this in relativity
As velocity increases, not only does time dilate - but you also get some other weird things.
Length of objects dilate, and mass increases
I don’t even know if we could tell that something is completely not moving at all - I think it would appear to be moving from our frame of reference - so how could we tell?[/quote]
You are right, as an object’s velocity increases, it’s mass also increases. As that velocity approaches the speed of light in a vacuum, it’s mass increases without bound. The most interesting thing about traveling at the speed of light in a vacuum is that the passage of time stops completely and concepts such as distance have no meaning at all. Einstein predicted this, but we have confirmed it experimentally. This means that from the reference point of an object traveling at the speed of light in a vacuum, all travel is instantaneous until it’s speed becomes less then the speed of light in a vacuum.
[/quote]
Maybe you could explain that thing in your avi. Not being able to wrap my mind around it is making my brain hurt.
[quote]Dr.Matt581 wrote:
[quote]squating_bear wrote:
I should probably keep my mouth shut on this (because I could be wrong), but I think I remember learning about this in relativity
As velocity increases, not only does time dilate - but you also get some other weird things.
Length of objects dilate, and mass increases
I don’t even know if we could tell that something is completely not moving at all - I think it would appear to be moving from our frame of reference - so how could we tell?[/quote]
You are right, as an object’s velocity increases, it’s mass also increases. As that velocity approaches the speed of light in a vacuum, it’s mass increases without bound. The most interesting thing about traveling at the speed of light in a vacuum is that the passage of time stops completely and concepts such as distance have no meaning at all. Einstein predicted this, but we have confirmed it experimentally. This means that from the reference point of an object traveling at the speed of light in a vacuum, all travel is instantaneous until it’s speed becomes less then the speed of light in a vacuum.
[/quote]
Well this thread is now hopelessly derailed…but into something fascinating, so I’m cool with it!
I am curious, would you tell me what experiment(s) confirmed the instantaneous reference point based travel you refer to?
Also, to whomever asked about objects exerting more gravity meaning faster rotation or some such, in addition to the good doc’s answer (inertia, as a function of mass, resists momentum more and more as mass increases), we have evidence of non-rotating black holes as well as rotating ones. So, as the most dense object known, it would follow that black holes would be rotating or moving fastest of all if gravity was responsible for increased speed or velocity of the object exerting it (not the outside objects it is acting on).
Finally, how do you contain the antimatter which you produce? In laymans terms of course, because I’m a chemistry geek not a physics doc. Do you contain it, while it exists, with plasma?
[quote]Aragorn wrote:
Well this thread is now hopelessly derailed…but into something fascinating, so I’m cool with it! [/quote]
This is the second thread I have derailed answering physics questions. Maybe someone should start a physics/science thread or something.
There have been a couple. I can’t remember who did this one right now, but when I do I will let you know. It involved studying photon propagation in materials with a refractive index not equal to one, meaning the photon will not be travelling at the speed of light in a vacuum, c. It was found that some of these photons would “decay” (The mechanisms of this so-called decay are a little complicated so I won’t go into them right now, but all photon’s experience them to an extent when propagating through material with a refractive index that is not equal to 1) over a period of time. When approaching c, the decay of photons slowed down due to time dilation and at c, no decay was observed until the photon was travelling at less than c.
The other experiment that I remember right now is the Double-slit experiment. Though not the point of the experiment, since the phenomenon had already been proven, the data can be used to show this phenomenon as well. If you know how to find solutions for complex partial differential equations I can walk you through a proof of it.
[quote] Also, to whomever asked about objects exerting more gravity meaning faster rotation or some such, in addition to the good doc’s answer (inertia, as a function of mass, resists momentum more and more as mass increases), we have evidence of non-rotating black holes as well as rotating ones. So, as the most dense object known, it would follow that black holes would be rotating or moving fastest of all if gravity was responsible for increased speed or velocity of the object exerting it (not the outside objects it is acting on).
Finally, how do you contain the antimatter which you produce? In laymans terms of course, because I’m a chemistry geek not a physics doc. Do you contain it, while it exists, with plasma? [/quote]
The thing about storing antimatter is that you have to prevent it from coming into contact matter of the matter and antimatter will destroy each other. For charged antimatter, this is usually done using a Penning Trap. Basically you have an airtight container with a vacuum with electric and magnetic fields induced in order to prevent the antimatter from coming into contact with matter.
For uncharged antimatter, some form of atomic trap is used, which operate using magnets and lasers to trap the antimatter.
[quote]Fletch1986 wrote:
[quote]Dr.Matt581 wrote:
[quote]squating_bear wrote:
I should probably keep my mouth shut on this (because I could be wrong), but I think I remember learning about this in relativity
As velocity increases, not only does time dilate - but you also get some other weird things.
Length of objects dilate, and mass increases
I don’t even know if we could tell that something is completely not moving at all - I think it would appear to be moving from our frame of reference - so how could we tell?[/quote]
You are right, as an object’s velocity increases, it’s mass also increases. As that velocity approaches the speed of light in a vacuum, it’s mass increases without bound. The most interesting thing about traveling at the speed of light in a vacuum is that the passage of time stops completely and concepts such as distance have no meaning at all. Einstein predicted this, but we have confirmed it experimentally. This means that from the reference point of an object traveling at the speed of light in a vacuum, all travel is instantaneous until it’s speed becomes less then the speed of light in a vacuum.
[/quote]
Maybe you could explain that thing in your avi. Not being able to wrap my mind around it is making my brain hurt.[/quote]
Page 2 on this thread should answer most of your questions on this.
So how does sound travel through extra-dimensional space? And did the universe exist as 1-dimensional space at first? And did it instantly go from 1-dimension to 4 instantaneously or did it go through stages if that’s right?
[quote][quote]Dr.Matt581 wrote:
[quote]Aragorn wrote:
Well this thread is now hopelessly derailed…but into something fascinating, so I’m cool with it! [/quote]
This is the second thread I have derailed answering physics questions. Maybe someone should start a physics/science thread or something.
There have been a couple. I can’t remember who did this one right now, but when I do I will let you know. It involved studying photon propagation in materials with a refractive index not equal to one, meaning the photon will not be travelling at the speed of light in a vacuum, c. It was found that some of these photons would “decay” (The mechanisms of this so-called decay are a little complicated so I won’t go into them right now, but all photon’s experience them to an extent when propagating through material with a refractive index that is not equal to 1) over a period of time. When approaching c, the decay of photons slowed down due to time dilation and at c, no decay was observed until the photon was travelling at less than c.
The other experiment that I remember right now is the Double-slit experiment. Though not the point of the experiment, since the phenomenon had already been proven, the data can be used to show this phenomenon as well. If you know how to find solutions for complex partial differential equations I can walk you through a proof of it.[/quote]
[quote] Also, to whomever asked about objects exerting more gravity meaning faster rotation or some such, in addition to the good doc’s answer (inertia, as a function of mass, resists momentum more and more as mass increases), we have evidence of non-rotating black holes as well as rotating ones. So, as the most dense object known, it would follow that black holes would be rotating or moving fastest of all if gravity was responsible for increased speed or velocity of the object exerting it (not the outside objects it is acting on).
Finally, how do you contain the antimatter which you produce? In laymans terms of course, because I’m a chemistry geek not a physics doc. Do you contain it, while it exists, with plasma? [/quote]
The thing about storing antimatter is that you have to prevent it from coming into contact matter of the matter and antimatter will destroy each other. For charged antimatter, this is usually done using a Penning Trap. Basically you have an airtight container with a vacuum with electric and magnetic fields induced in order to prevent the antimatter from coming into contact with matter.
For uncharged antimatter, some form of atomic trap is used, which operate using magnets and lasers to trap the antimatter.[/quote]
Well, I am rusty on diff eq., but I’ll take a walkthrough. I’m sure it will come back to me as I read through. Regarding the photon decay rate, that’s a pretty neat experiment to run.
I should have seen that coming. I was thinking of an analogous way to that of containing plasma with magnetic and electric fields, but totally phrased that wrong. Is there a name for the kind of containment used on uncharged antimatter?
Dr. Matt is there something like a book or a website on physics that would give a basic or sort of broad understanding of Physics and what it takes to major in and possibly what job opportunities are out there for Physics majors? Did you also get a degree or minor in mathematics? Math and physics appear to go well together from what I’ve heard.
I have a friend who is interested in majoring in Physics but he doesn’t know if it’s something he’d be interested in long term, what job opportunities are out there, and if he’s smart enough to do it. Figure there has to be a book or something out there that can give him a basic overview of Physics so he has a better idea about it.
[quote]MaximusB wrote:
I love Bill Clinton posing with some porn stars…
Jennifer Taule, Tasha Reign, Brooklyn Lee :)[/quote]
And he makes it look effortless too though I am sure that this is totally alien to his character.
[quote]Fletch1986 wrote:
So how does sound travel through extra-dimensional space? [/quote]
If there are other dimensions in our universe, they exist alongside with the 4 that we know about so wave propagation is the same as it always has been. If and when we can confirm and observe other dimensions, our understanding of wave propagation may change and we would then have to describe wave behavior differently though. Without being able to observe and measure such phenomena, I can’t say definitively what would change, but I doubt it would be anything significant.
According to the prevailing theories, the universe was indeed at one point a dimensionless singularity. The transition from dimensionless to 4 dimensions was not instantaneous, but the time interval involved (Something like less then 10^-36 seconds) is so small it can be thought of as instantaneous.
[quote]Aragorn wrote:
Well, I am rusty on diff eq., but I’ll take a walkthrough. I’m sure it will come back to me as I read through. Regarding the photon decay rate, that’s a pretty neat experiment to run.
I should have seen that coming. I was thinking of an analogous way to that of containing plasma with magnetic and electric fields, but totally phrased that wrong. Is there a name for the kind of containment used on uncharged antimatter?[/quote]
There are several types of atomic traps, so they are usually just referred to as atomic or magnetic traps. Give me some time on that proof, I need to look up the data from the experiment and finding solutions to quantum wave functions is a little time consuming.
[quote]Grimlorn wrote:
Dr. Matt is there something like a book or a website on physics that would give a basic or sort of broad understanding of Physics and what it takes to major in and possibly what job opportunities are out there for Physics majors? Did you also get a degree or minor in mathematics? Math and physics appear to go well together from what I’ve heard.
I have a friend who is interested in majoring in Physics but he doesn’t know if it’s something he’d be interested in long term, what job opportunities are out there, and if he’s smart enough to do it. Figure there has to be a book or something out there that can give him a basic overview of Physics so he has a better idea about it.[/quote]
I do not know of any books like that, but if you want to find out if you may want to major in physics then I would recommend just taking the standard 3 semester calculus and 3 semester calculus-based physics sequence. If you start in the fall semester and take calc 3 and physics 3 over the summer it is not much time and even if you decide on another field of study the math and problem solving skills that you learn in just those introductory classes will put you far above your classmates that have not done that and will make a huge difference in your education and life in general. I actually think those courses should be required of all students whether they are majoring in the hard sciences, philosophy, english, or business, or anything else. Even if you decide on a different scientific field, most will require at least a semester or two of basic calculus, the same for engineering. Even if your friend decides on a liberal arts degree, those classes will satisfy math, science, and elective options so it is not going to be a waste.
I would caution your friend not to decide on majoring in physics until taking an intro to differential equations class and calc 3. Once you get past the basic calculus based physics sequence, virtually all the physics classes heavily involve multivariable and vector calculus, which is calc 3, and/or a lot of differential equations. If those classes did not appeal to him then he will not enjoy being a physicist. If he still likes the hard sciences, but does not like the higher math then he may want to consider engineering or a different scientific discipline that does not deal as heavily in higher mathematics. Many other scientific fields do require at least 2 or 3 semesters of calculus though.
If your friend does decide to major in physics, he will be in a very good position to do just about anything he wants to do. He should choose his minor, or minors wisely just in case he decides not to go to grad school or does not manage to attain a PhD. With just a standard physics degree, he will be qualified for most engineering jobs and eventually take the PE exam regardless of his minor, but with a minor in computer science or business (I recommend both) then he will be qualified for most computer science/programming jobs. Other potential jobs are teaching at the high school or maybe community college level, or working for a research team (this usually requires at least a master’s degree.
As for your friend not knowing if he is smart enough to major in physics, you do not need to be a genius to do it. The problem most people have with physics and calculus is the math skills needed. Most people entering college in the past decade or so in the US have extremely poor math skills and it takes time and effort to develop them. It doesn’t help that overall study skills have been declining as well. Physics and higher math classes take time and effort to master them and most students would rather spend their time partying, watching TV, playing video games, or messing around on facebook or some shit like that. He will have to sacrifice some of his personal life in order to get a degree in a difficult subject like physics. As an extreme example of this, I had two BS and two master’s degrees before I ever went out on a date. Like I said, that is an extreme example and not the norm, but it makes my point. He needs to look at the long term course of his education and his life goals. Even with just a BS in physics, he is looking at making quite a bit more then the average college graduate over the entire course of his career. If he is not willing stay in on Friday or Saturday night and study instead of going out during the semester or just vegging out on the couch, then physics is not the major for him.
Yes, math and physics are very closely related. Most physics programs actually fulfill most of the requirements for a degree in applied mathematics. I recommend to all of the physics majors at my school that they go ahead and do a double major since it does not take much more work. When I was an undergrad, I only had to take 4 extra classes to get a BS in applied math, so I went ahead and did it. When I was getting my PhD, I had to take a lot of graduate level mathematics classes and realized that I already had all the credits I needed to get a master’s degree in applied mathematics. All I had to do was complete a master’s thesis which I did in two semesters. I actually only need about 20 more credits, and a dissertation, in order to get a PhD in applied mathematics, but there is no point since I have no desire to switch from being a physicist to a mathematician.
One of the reasons I went into environmental science instead of engineering is the math. Once the courses started getting into anti-derivatives, I just couldn’t keep up. I’d work my ass off to get a C and I only saw it getting more difficult.
[quote]Fletch1986 wrote:
One of the reasons I went into environmental science instead of engineering is the math. Once the courses started getting into anti-derivatives, I just couldn’t keep up. I’d work my ass off to get a C and I only saw it getting more difficult.[/quote]
Yeah, Calc 2 is by far the most difficult of the 3 intro courses that I took. Calc 1 is a piece of cake, if you have a little mental calisthenics in you for the concepts. Calc2, with almost the entire course being anti-derivatives (integrals) and different ways of solving them, was a bitch. I attribute this mostly to the fact that it is like the difference between learning the concepts behind how an internal combustion engine breaks down (carb sync problem, flooding of an engine, vacuum leaks or fuel injection problems, thermostat problems)–which is mostly easy conceptually…and then learning what tools are necessary to actually break down the engine and fix the problem (1,000 different wrenches, sockets, bolts, etc) and which to use when. That is a much more difficult job than just learning the concepts.
It is like learning a new language–what are the patterns? when can you use this tool or that tool? That’s Calc 2 and that’s why it’s so damn difficult for most people, myself included. I found Calc 3 much easier–taking Calc 2 and expanding it to 3 dimensional objects (in laymans terms) was loads easier than actually learning the vocabulary and tools in the first place.
Dr. Matt is right though–take at least the first 2 calc and calc based physics courses. I always thought I’d never really need them but the skills they taught made every other subject (even chemistry) much easier to deal with while most of my classmates were struggling. I certainly had a social life in college :). But I did stay in on many pleasant days in spring and study for the next test too. I firmly believe it paid more than it’s share in the long run.
As a side note, most of the interesting stuff in physics doesn’t happen until the 3rd course (which is usually intro to relativity and quantum, at least in my university). I wasn’t really thrilled with projectile motion or magnetic fields…until things get crazy in time and space, then I’m all over that. 
But that is just my personal taste. There were actually many interesting things in the first two courses.
[quote]Aragorn wrote:
[quote]Fletch1986 wrote:
One of the reasons I went into environmental science instead of engineering is the math. Once the courses started getting into anti-derivatives, I just couldn’t keep up. I’d work my ass off to get a C and I only saw it getting more difficult.[/quote]
Yeah, Calc 2 is by far the most difficult of the 3 intro courses that I took. Calc 1 is a piece of cake, if you have a little mental calisthenics in you for the concepts. Calc2, with almost the entire course being anti-derivatives (integrals) and different ways of solving them, was a bitch. I attribute this mostly to the fact that it is like the difference between learning the concepts behind how an internal combustion engine breaks down (carb sync problem, flooding of an engine, vacuum leaks or fuel injection problems, thermostat problems)–which is mostly easy conceptually…and then learning what tools are necessary to actually break down the engine and fix the problem (1,000 different wrenches, sockets, bolts, etc) and which to use when. That is a much more difficult job than just learning the concepts.
It is like learning a new language–what are the patterns? when can you use this tool or that tool? That’s Calc 2 and that’s why it’s so damn difficult for most people, myself included. I found Calc 3 much easier–taking Calc 2 and expanding it to 3 dimensional objects (in laymans terms) was loads easier than actually learning the vocabulary and tools in the first place.
Dr. Matt is right though–take at least the first 2 calc and calc based physics courses. I always thought I’d never really need them but the skills they taught made every other subject (even chemistry) much easier to deal with while most of my classmates were struggling. I certainly had a social life in college :). But I did stay in on many pleasant days in spring and study for the next test too. I firmly believe it paid more than it’s share in the long run.[/quote]
Calc 2 is probably the most difficult undergrad math class there is, but also one of the most useful. Sure, classes like partial differential equations and computational methods cover more complicated topics, but calc 2 really is where most of the lower math skills (geometry, algebra, trigonometry, etc.) are solidified and actually used to solve real problems and also where advanced problem solving and critical thinking skills are developed. My Achilles Heel in calc 2 was Power Series. I really wish it would be made a required general education class. I guarantee the quality of education and the quality of students in general would go way up.
[quote]Aragorn wrote:
As a side note, most of the interesting stuff in physics doesn’t happen until the 3rd course (which is usually intro to relativity and quantum, at least in my university). I wasn’t really thrilled with projectile motion or magnetic fields…until things get crazy in time and space, then I’m all over that. But that is just my personal taste. There were actually many interesting things in the first two courses.[/quote]
That used to be the norm, but in recent years there has been a trend towards just covering the standard classical topics (Newtonian mechanics, E&M, Thermodynamics, which is personally my least favorite, Waves, and optics) in the standard 3 course intro classes while completing up to an intro to differential equations and linear algebra(the sophomore level ones)course/courses. After that, a 2 semester intro to modern physics sequence, which covers the basics of relativity, quantum mechanics, nuclear physics, and selected topics, is done. The reasoning for this is that all modern physics topics require a basic understanding of differential equations to really understand them. Just as an example, Schrodinger’s equation is to quantum mechanics what Newton’s Second law (F=ma) is to classical mechanics. Could you imagine trying to understand mechanics if you couldn’t figure out how to manipulate and understand that equation? I can’t. The same thing applies to quantum mechanics and Schrodinger’s equation, which is a linear complex partial differential equation. The ‘complex’ refers to complex numbers, by the way, not that the equations are particularly difficult, even though they usually are. It just means that solutions to Schrodinger’s equation include imaginary numbers.
Once that is done, those classes, classical and modern are usually done again, with each topic getting a whole semester instead of just a few weeks, with vector calculus and diff eq and linear algebra used as problem solving tools and a more in depth understanding of the concepts are developed. It is the same process for grad school except even higher math skills, like differential geometry, are used and the concepts of those topics are covered even more in depth.