I Transition between energy and mass

[Robin04]

How well is the transition between energy and mass understood? Energy can turn into matter and matter can turn into energy but what is actually happening between the two states? Imagining that matter just simply appears and disappears under an infinitesimal amount of time feels weird to me.

 

[Orodruin]

Energy can turn into matter and matter can turn into energy but what is actually happening between the two states?

This is just not a good description. Nothing can ”turn into energy” as energy is a property, not a substance.

 

[Robin04]

This is just not a good description. Nothing can ”turn into energy” as energy is a property, not a substance.

Then maybe I’m misunderstanding the mass-energy equivalence? What does it actually say in this context?

 

[Orodruin]

The mass-energy equivalence relates the rest-energy of an object with its classical inertia. In other words, how much an object resists acceleration in its rest-frame depends on how much energy it has in that frame. Einstein's original paper on the mass-energy equivalence was titled "Ist die Trägheit eines Körpers von seinem Energiegehalt abhängig?", which translates to "Does the inertia of a body depend upon its energy-content?" Unlike many other physics papers with a question in the title, the answer to this title was "yes".

The point is that, if you transform a system, such as a decaying nucleus, into a system consisting of particles that in total have less rest energy (i.e., mass), then some energy must go into other forms of energy - such as kinetic energy - for energy to be conserved.

 

[Vanadium 50]

what is actually happening

Suppose we said "what is actually happening is X". Wouldn't yout next question be, "Yeah, but what is actually happening with X?" We answer Y, and it never ends. We are not equipped to answer what is actually actually actually actually happening. At best we can describe how the world we live in seems to behave.

feels weird to me

The universe is under no obligation to arrange itself in a way that doesn't.

 

[DrStupid]

Then maybe I’m misunderstanding the mass-energy equivalence? What does it actually say in this context?

The mass-energy equivalence says that for any rest energy there is an equivalent amount of mass and vice versa. If the rest energy of a system changes than its mass changes as well. This can only happen by exchange of energy or momentum with the environment and not by internal processes (including pair production or annihilation).

 

[Robin04]

I have to admit that my question resulted from a serious misunderstanding of the concept of energy. I imagined it as a state of "something" that can be in the form of matter as well. Just like a solid can turn into liquid and back. So if I get it this time, energy is more abstract than that, not sure I understand what it really is, but at least now I know what to look for.

Suppose we said "what is actually happening is X". Wouldn't yout next question be, "Yeah, but what is actually happening with X?" We answer Y, and it never ends. We are not equipped to answer what is actually actually actually actually happening. At best we can describe how the world we live in seems to behave.

Yes, I know that we can always keep asking questions forever, try to dig deeper and look for what is beyond out current knowledge, and in this sense a paradigm determines what questions are reasonable and what aren't in order to drive scientific work. But in the course of development we are actually digging deeper and encounter things we have never thought about before (for example the discovery that the atom is not the smallest unit as we thought before). However, I admit that these do not happen along asking "rebel" questions as I did, but more along doing experiments or a proved theory that predicts something odd.

The universe is under no obligation to arrange itself in a way that doesn't.

Well, you got me. What made me brave enough to say that I feel weird about something in nature is that I see some physicists too who express similar doubts. For example Lee Smolin says in his book called The Trouble With Physics that the fact that quantum mechanics doesn't make sense can be an obstacle to constructing quantum gravity and maybe we have to do something with it.

 

[ZapperZ]

Well, you got me. What made me brave enough to say that I feel weird about something in nature is that I see some physicists too who express similar doubts. For example Lee Smolin says in his book called The Trouble With Physics that the fact that quantum mechanics doesn't make sense can be an obstacle to constructing quantum gravity and maybe we have to do something with it.

Unfortunately, this is now getting into a matter of personal taste. Saying something "doesn't make sense" doesn't say much, because I can easily show you a bunch of people telling me that time slowing down in a moving reference frame "doesn't make sense". I also love eating fish heads ("eat them up, yum!") and many people tell me that that doesn't make sense. I tell them that their love for White Castle doesn't make sense to me.

Do you see what I'm getting at?

Science can never be challenged simply because "it doesn't make sense", because "making sense" is nothing more than a set of knowledge that a person has acquired, and is familiar with. So naturally, something that is beyond that set of knowledge, and something that isn't familiar, will automatically makes no sense to that person. Science can only be challenged and changed if it is not logically consistent, or if there are empirical evidence to the contrary. That's it!

Zz.

 

[Robin04]

Unfortunately, this is now getting into a matter of personal taste. Saying something "doesn't make sense" doesn't say much, because I can easily show you a bunch of people telling me that time slowing down in a moving reference frame "doesn't make sense". I also love eating fish heads ("eat them up, yum!") and many people tell me that that doesn't make sense. I tell them that their love for White Castle doesn't make sense to me.

Do you see what I'm getting at?

Science can never be challenged simply because "it doesn't make sense", because "making sense" is nothing more than a set of knowledge that a person has acquired, and is familiar with. So naturally, something that is beyond that set of knowledge, and something that isn't familiar, will automatically makes no sense to that person. Science can only be challenged and changed if it is not logically consistent, or if there are empirical evidence to the contrary. That's it!

Zz.

Do you mean this for my main question (which was based on me feeling weird) or for the example of quantum mechanics not making sense when it comes to unifying it into quantum gravity?

Asking a question only out of a weird feeling and nothing else was for sure a mistake from my part and you're right that normal scientific work cannot be based on such arbitrary personal taste.

But I think that when it comes to the leading edge of science, personal taste has a very important effect on scientific research and also the distinction between the matter of personal taste and logical inconsistency is not the clear either. Quantum mechanics is a proved and working science, no doubt about that, but its unification with general relativity into quantum gravity is not obvious at all. Very different opinions appear about how it should be done and everybody works on their own idea until there's no consensus about which direction we should take. These different ideas come from personal taste and some formulate logical inconsistencies too. For example a big difference between general relativity and quantum mechanics is that they use a different concept of space and time yet they're supposed to talk about the same thing. Of course there's lot to be done and most of these ideas are going to come to a dead end but I think that in the present period of the problem it is valid for scientific research to be based on personal taste to some extent. Later, once the revolution finished we can come back to working on problems which are given precisely by the new paradigm without the influence of any arbitrariness.

 

[ZapperZ]

Do you mean this for my main question (which was based on me feeling weird) or for the example of quantum mechanics not making sense when it comes to unifying it into quantum gravity?

Asking a question only out of a weird feeling and nothing else was for sure a mistake from my part and you're right that normal scientific work cannot be based on such arbitrary personal taste.

But I think that when it comes to the leading edge of science, personal taste has a very important effect on scientific research and also the distinction between the matter of personal taste and logical inconsistency is not the clear either. Quantum mechanics is a proved and working science, no doubt about that, but its unification with general relativity into quantum gravity is not obvious at all. Very different opinions appear about how it should be done and everybody works on their own idea until there's no consensus about which direction we should take. These different ideas come from personal taste and some formulate logical inconsistencies too. For example a big difference between general relativity and quantum mechanics is that they use a different concept of space and time yet they're supposed to talk about the same thing. Of course there's lot to be done and most of these ideas are going to come to a dead end but I think that in the present period of the problem it is valid for scientific research to be based on personal taste to some extent. Later, once the revolution finished we can come back to working on problems which are given precisely by the new paradigm without the influence of any arbitrariness.

There is a difference between adopting a point of view on research-front areas versus trying to question about established physics simply based on what "makes sense". Your original post was all about questioning something that is well-established based on what you found to be "weird". THIS is what I was addressing.

Research-front topics is a different animal entirely. I was involved heavily during the heydays of research in high-Tc superconductors. Even until today, there are still competing theories on the fundamental mechanisms of superconductivity in those material. Different camps have different ideologies that they follow. This is not unusual, because the experimental data that we have are still not very convincing enough to sort things out just yet. But eventually they will, and it will no longer become simply as a matter of tastes. This is not what I addressed, and I highly doubt that your understanding of any parts of physics is that deep that you are able to offer an educated opinion of something that you found "weird", are you?

I do not understand what you are trying to accomplish here. Are you seriously questioning something simply because it looks weird to you, and using solely THAT as your criteria?

As your level, why don't you grab a helium balloon that is attached to a string, go inside a closed vehicle or a train, or a bus, and then see what happens when the vehicle accelerates or decelerates. See if you find something "weird" happening to that balloon. Then ask yourself whether it is really "weird", or is it just because you just did not understand what exactly is going on that you THINK it is weird?

Zz.

 

[berkeman]

As your level, why don't you grab a helium balloon that is attached to a string, go inside a closed vehicle or a train, or a bus, and then see what happens when the vehicle accelerates or decelerates. See if you find something "weird" happening to that balloon. Then ask yourself whether it is really "weird", or is it just because you just did not understand what exactly is going on that you THINK it is weird?

Yes, what happens is indeed weird! I got that wrong on a physics test one time...

 

[Robin04]

I think we misunderstood each other. Maybe I didn't express my point clearly enough, so let me try again.

Unfortunately, this is now getting into a matter of personal taste. Saying something "doesn't make sense" doesn't say much, because I can easily show you a bunch of people telling me that time slowing down in a moving reference frame "doesn't make sense". I also love eating fish heads ("eat them up, yum!") and many people tell me that that doesn't make sense. I tell them that their love for White Castle doesn't make sense to me.

Do you see what I'm getting at?

Science can never be challenged simply because "it doesn't make sense", because "making sense" is nothing more than a set of knowledge that a person has acquired, and is familiar with. So naturally, something that is beyond that set of knowledge, and something that isn't familiar, will automatically makes no sense to that person. Science can only be challenged and changed if it is not logically consistent, or if there are empirical evidence to the contrary. That's it!

You had this comment. I didn't understand at first whether you mean this for me asking a question just because of feeling weird about something or you reflect on my example of quantum mechanics, so I answered both cases.

First case:

Asking a question only out of a weird feeling and nothing else was for sure a mistake from my part and you're right that normal scientific work cannot be based on such arbitrary personal taste.

As you can see, I admitted my mistake. I don't understand why your last comment is still mostly about this. I learned that I cannot question physics just because it feels weird at first. Moreover, the question itself was incorrect in content, because I misunderstood what energy is. I'm aware of my level of knowledge, or I'm trying to be at least. I haven't even started university, I still have a lot to learn, but I do have thoughts about science. Yes, most of them are incorrect, stupid, childish, whatever, but I don't want this to hold me back from telling them, because that's one of the best ways to learn. In my country, the teacher:student ratio is very low, so relationships between students and teachers are very distant, and it rarely occurs that teachers have time to reflect on student's thoughts about sciences in general, yet it would be important. I think that PF is a really good platform to help with this as it's full of educated professionals, so thank you very much for being here and helping me.

As for the second case, if I understand your answer well, I think we agree so this part is not a bone of contention anymore.

I was involved heavily during the heydays of research in high-Tc superconductors. Even until today, there are still competing theories on the fundamental mechanisms of superconductivity in those material. Different camps have different ideologies that they follow. This is not unusual, because the experimental data that we have are still not very convincing enough to sort things out just yet. But eventually they will, and it will no longer become simply as a matter of tastes.

 

[cosmik debris]

Asking a question only out of a weird feeling and nothing else was for sure a mistake from my part and you're right that normal scientific work cannot be based on such arbitrary personal taste.

I'm not sure that it was a mistake. After all something, a gut feeling maybe, points you to ask a question. It may turn out either to confirm or deny your intuition but something has to motivate an investigation.

Cheers

 

[Robin04]

Reading through the thread after a few days makes me feel that I was a bit narcissistic and disrespectful. I sincerely apologize, I'll try to pay attention to that in the future, and thank you very much for you help!