- #1
Lou Arnold
- 11
- 0
I'm a retired Engineer. I want to learn methods to formulate equations to ask questions of physics phenomenon. What school teaches this and by whom? Can anyone point me there?
Looking for an emoticon to mark a reaction, I find none that I really want. When someone responds to your question, that and maybe other posts could be interesting.Lou Arnold said:I'm a retired Engineer. I want to learn methods to formulate equations to ask questions of physics phenomenon. What school teaches this and by whom? Can anyone point me there?
I want to ask the same thing. What does @Lou Arnold really want to know or understand. Retired Engineer means he is experienced and educated, so has used Mathematics to explore and make decisions with the use of Physics and whatever Mathematics which describes concepts and past-used applications. One would believe he has already learned to do much of what he may be trying to ask. @Lou Arnold, maybe the connection between Physics and Engineering has not been very clear for you? But if this, then readers very possibly do not understand how these are disconnected for you.malawi_glenn said:Can you provide an example? I have no idea what you are after
I doubt you need a course to learn that. It's one line of algebra, surely?Lou Arnold said:Given the equation of a pendulum, how to find the length that gives a specific frequency of oscillation? i have never seen a course that teaches how to formulate this in an equation.
It is in Hartle's book:Lou Arnold said:This may be simple for this problem, but is more complex when you want to use General Relativity equations to find the degree light is bent coming from a star around the sun.
And no this information does not exist in Schutz's book.
Are you already comfortable with Lagrangian mechanics?Lou Arnold said:I understand the typical equations that are taught in undergrad and graduate physics. These equations describe the static and dynamic behaviour of physical phenomenon. However, when one wants to ask a question of this phenomenon, how does one use these equations - i.e. the goal is to formulate an equation which when solved, gives a answer.
Look. The pendulum problem is a simple example. I don't need the solution. I need a plan of attack that works in general. Try the light bending problem that I meantioned. Try Langrangians for that.berkeman said:Are you already comfortable with Lagrangian mechanics?
https://en.wikipedia.org/wiki/Lagrangian_mechanics
Did you not think that I already knew that method?? Can you not take the question further?gmax137 said:Do you mean, given:
$$ T=2 \pi \sqrt{\frac L g} $$
Here T is the period, the inverse of the frequency. Use Algebra, solve for L
$$L=g \left(\frac {T} {2 \pi} \right)^2$$
I'm sure you know this, makes it hard to understand your question.
Just to clarify: You are looking for a general method to solve any problem? I doubt that one exists. If it did theoreticians would be out of a job!Lou Arnold said:Look. The pendulum problem is a simple example. I don't need the solution. I need a plan of attack that works in general. Try the light bending problem that I meantioned. Try Langrangians for that.
How should anybody of us know? You left us guessing due to your imprecise descriptions. It really sounds as if you wanted to studyLou Arnold said:Did you not think that I already knew that method?? Can you not take the question further?
PeroK said:I doubt you need a course to learn that. It's one line of algebra, surely?
Do you read the answers you receive?Lou Arnold said:Try the light bending problem that I meantioned.
PeroK said:
Yes, I know it looks different when you read our threads on PF. The fact is, however, that we do not have crystal balls.Lou Arnold said:Did you not think that I already knew that method?
fresh_42 said:How should anybody of us know? You left us guessing due to your imprecise descriptions. It really sounds as if you wanted to study
Do you read the answers you receive?
I, too, read your contributions like the question: "How can I learn to rearrange problems such that B instead of A is asked?"Yes, I know it looks different when you read our threads on PF. The fact is, however, that we do not have crystal balls.
If you really study a certain theory, then it won't play a role from which perspective you look at it. But generally, it cannot be ruled out that some problems become unsolvable if seen from the other side. I doubt that there is a book about such a general approach.
Well, a "method" is perhaps a misnomer. I would call it an "approach". I'm surprised that no one seems to have asked this same question - how to ask a mathematical question -somtimes when the equations seem not to have a formulation that doesn't even mention the information wanted. It seems such an essential method of testing physics. But how do "I" get better at this if I don't ask how to ask?topsquark said:Just to clarify: You are looking for a general method to solve any problem? I doubt that one exists. If it did theoreticians would be out of a job!
-Dan
Question well to the point. I have a software engineering background. Its my problem to program those mathematical questions, but all through my physics courses no one even thought about asking mathematical questions. From all the material I see taught, it teaches the HISTORY of physics and not the physics itself simply becuase you can't experiment with the defining equations. The Schrodinger wave equation is a perfect example. It was simply presented and that's all.CrysPhys said:OP: What is your background in engineering? Didn't you face a similar situation in engineering? That is, you learned various equations applicable to particular model systems. Then when you were faced with a particular problem to solve, you had to decide which particular model systems were applicable and which particular equations were applicable.
Yes, but the equations didn't necessarily contain variables that gave the information. It was not simply a matter of solving for variables.CrysPhys said:OP: What is your background in engineering? Didn't you face a similar situation in engineering? That is, you learned various equations applicable to particular model systems. Then when you were faced with a particular problem to solve, you had to decide which particular model systems were applicable and which particular equations were applicable.
But there may be a course. Someone must have considered this matter before me. How do experimental physicists test problems if they can't ask questions using the defining equations? After all. the GR equations can't directly be solved for the angle that light is bent through. Nor can Schwartzchild's solutions be used to ask that question.fresh_42 said:How should anybody of us know? You left us guessing due to your imprecise descriptions. It really sounds as if you wanted to study
Do you read the answers you receive?
I, too, read your contributions like the question: "How can I learn to rearrange problems such that B instead of A is asked?"Yes, I know it looks different when you read our threads on PF. The fact is, however, that we do not have crystal balls.
If you really study a certain theory, then it won't play a role from which perspective you look at it. But generally, it cannot be ruled out that some problems become unsolvable if seen from the other side. I doubt that there is a book about such a general approach.
Is the question how do physicists devise experiments to test a theory? Sometimes it must be obvious - like the pendulum, where you simply time pendulums of different masses and lengths. Sometimes it's not so obvious - the Schrodinger equation and its solutions for energy levels are tested indirectly by measuring the emission and absorption spectrum of hydrogen. Sometimes it takes an insight amounting to genius - such as Bell's theorem to test quantum entanglement against local hidden variable theories.Lou Arnold said:I read the answers, but I can't get Hartle at this time and so I can't determine of the book shows how to ask questions
1. My question is: how do physicists calculate expected results for a future experiments.PeroK said:Is the question how do physicists devise experiments to test a theory? Sometimes it must be obvious - like the pendulum, where you simply time pendulums of different masses and lengths. Sometimes it's not so obvious - the Schrodinger equation and its solutions for energy levels are tested indirectly by measuring the emission and absorption spectrum of hydrogen. Sometimes it takes an insight amounting to genius - such as Bell's theorem to test quantum entanglement against local hidden variable theories.
The deflection of light is a somewhat complicated calculation, although the concept is clear enough. And a lot of modern physics is tested through calculating the cross sections of particle interactions, which involves yet more complicated calculations.
The books I've studied from tend to have a mixture of theory and calculations explicitly for experimental purposes. It's all part and parcel of learning physics.
It is not as if there was nothing out there:Lou Arnold said:1. My question is: how do physicists calculate expected results for a future experiments.
2. What are those books?
Is that true?Lou Arnold said:After all. the GR equations can't directly be solved for the angle that light is bent through.
Are you basically asking for resources/classes/books about how to invent new things? I can offer some insights on that question, if that is what you are asking in general...Lou Arnold said:But there may be a course. Someone must have considered this matter before me. How do experimental physicists test problems if they can't ask questions using the defining equations?
No. Neither.fresh_42 said:Could it be that you have to some extent a theory and you are now looking for a prediction to test it?
Am I right that you are a string theorist?
Nothing to do with invention. The best example of problem that might interest me is the calculation of the degree of bending of a light bean from a star as the beam passes the sun. All one has for that are the Einstein equations. Einstein and Eddington calculated some 3 to 6 possible answers but don't say what approximations they used and why.berkeman said:Is that true?Are you basically asking for resources/classes/books about how to invent new things? I can offer some insights on that question, if that is what you are asking in general...
As already noted by several people responding in this thread, the above is very confusing. Physicists don't formulate equations in order to ask questions; they formulate equations in order to explain, or model, physics phenomena (plural of phenomenon).Lou Arnold said:I want to learn methods to formulate equations to ask questions of physics phenomenon.
While I don't know what schools, I did some regression analysis in my training. Back when I was working as an analyst programmer in GIS, I had to do a run time optimisation of a data analysis between map layers. This was taking a prohibitively long run time on large data sets. So, I gathered run time data in Excel & used the regression analysis tools there. There are several basic regression curve types available, linear, exponential etc, based on curve power. If you run the same data set through the available options, the one with the highest correlation coefficient is the mathematical expression that best describes your data.Lou Arnold said:I'm a retired Engineer. I want to learn methods to formulate equations to ask questions of physics phenomenon. What school teaches this and by whom? Can anyone point me there?
Vanadium 50 said:I just reread the Eddington paper (which has a co-author F. Dyson - and not the one you are likely thinking of) and it was a delight. What I did not see any reference to multiple GR predictions.
One would be curious of what your education was. A person who earned a degree, especially an advanced degree, in a Natural Science or a Physical Science would have had those questions satisfactorily answered a long time ago. As for graduates of Engineering or Computer Science, I (myself) would not guess about it.Lou Arnold said:1. My question is: how do physicists calculate expected results for a future experiments.
2. What are those books?
The purpose of using mathematical equations in physics is to describe and quantify the relationships between physical quantities and phenomena. It allows us to make predictions and understand the behavior of the natural world.
Mathematical equations in physics are typically taught by physics professors or instructors in universities or colleges. They may also be taught by high school physics teachers or through online resources.
The difficulty of learning mathematical equations in physics can vary depending on the individual's mathematical background and the complexity of the equations being taught. With proper instruction and practice, anyone can learn and understand these equations.
Some common mathematical equations used in physics include Newton's laws of motion, the equations of motion, the laws of thermodynamics, and Maxwell's equations. There are also many other equations specific to different branches of physics.
To improve your skills in using mathematical equations in physics, it is important to have a strong foundation in mathematics, practice regularly, and seek help from a teacher or tutor if needed. It can also be helpful to work through example problems and apply the equations to real-world situations.