GeneralDadmission Posted February 26, 2015 Posted February 26, 2015 What is the difference between an elements normal rest mass and the mass it accumulates as a result of acceleration?
ajb Posted February 26, 2015 Posted February 26, 2015 I assume you are asking about rest mass and relativistic mass? Or do you mean something else? Anyway, in modern physics people tend to stick with just the rest mass as being the mass.
imatfaal Posted February 26, 2015 Posted February 26, 2015 What is the difference between an elements normal rest mass and the mass it accumulates as a result of acceleration? You need to tread very carefully when dealing with mass - ie checking which frame of reference you are talking about. For starters it is relative velocity not acceleration that in certain usages of mass will lead to a change. And secondly invariant mass - which is the useful one - is the same in all frames of reference
GeneralDadmission Posted February 26, 2015 Author Posted February 26, 2015 You need to tread very carefully when dealing with mass - ie checking which frame of reference you are talking about. For starters it is relative velocity not acceleration that in certain usages of mass will lead to a change. And secondly invariant mass - which is the useful one - is the same in all frames of reference I'm not assuming anything upon change. I'm asking whether the volume of mass energy in a given element at a given velocity could be used to analyse another hypothesised particle.
ajb Posted February 26, 2015 Posted February 26, 2015 I'm not assuming anything upon change. I'm asking whether the volume of mass energy in a given element at a given velocity could be used to analyse another hypothesised particle. I am sorry, but this is just gibberish.
GeneralDadmission Posted February 26, 2015 Author Posted February 26, 2015 (edited) why can you not analyse the rest mass of the DM particle against the mass of a standard element at a certain velocity? It really doesn't seem that difficult a question to decipher Edited February 26, 2015 by GeneralDadmission
swansont Posted February 26, 2015 Posted February 26, 2015 There is no such thing as a volume of mass energy. Energy is a property of things. You can specify an energy density, which would be the energy per unit volume. The mass energy something has is independent of speed, unless you redefine mass to be relativistic mass, which is just a proxy for the total energy. Energy as a function of speed is given by [math]\gamma mc^2[/math] why can you not analyse the rest mass of the DM particle against the mass of a standard element at a certain velocity? It really doesn't seem that difficult a question to decipher That's not the same question. AFAIK, we don't know what the rest mass is of a DM particle, since we don't yet know what DM is. We know some things it isn't, though.
GeneralDadmission Posted February 26, 2015 Author Posted February 26, 2015 (edited) There is no such thing as a volume of mass energy. Energy is a property of things. You can specify an energy density, which would be the energy per unit volume. The mass energy something has is independent of speed, unless you redefine mass to be relativistic mass, which is just a proxy for the total energy. Energy as a function of speed is given by [math]\gamma mc^2[/math] That's not the same question. AFAIK, we don't know what the rest mass is of a DM particle, since we don't yet know what DM is. We know some things it isn't, though. So it is assumed it is a high mass particle.That mass has to represent some sort of balance, as hydrogen and helium and every other element. Because it is helium that stabilises inflation I believe it is an appropriate particle to approximate the DM particles properties against. The basic approach I have taken to defining this is to question whether it is a particle that reflects a helium particle with a high velocity. I do not automatically assume that DM is a helium particle travelling very fast. Edited February 26, 2015 by GeneralDadmission
swansont Posted February 26, 2015 Posted February 26, 2015 So it is assumed it is a high mass particle. Who assumes this? That mass has to represent some sort of balance, as hydrogen and helium and every other element. Because it is helium that stabilises inflation I believe it is an appropriate particle to approximate the DM particles properties against. The basic approach I have taken to defining this is to question whether it is a particle that reflects a helium particle with a high velocity. I do not automatically assume that DM is a helium particle travelling very fast. Helium stabilizes inflation? It has been repeatedly pointed out that He cannot be DM. If you are not assuming this and yet questioning whether it can be true (I'm not seeing much of a distinction), a question to consider would be what physics leads you to believe that this is the case. A question to be addressed in speculations, of course, since this thread is on another topic and is about mainstream physics. What is on-topic is the notion that "moving very fast" matters. Motion is relative — moving fast relative to what? Why should this matter? Physics is unchanged by the choice of reference frame. It still works in the frame where the particle is at rest (and it's often easier to do physics in that frame). Motion does not change the rest mass, which is invariant.
GeneralDadmission Posted February 26, 2015 Author Posted February 26, 2015 I JUST SAID I DON"T THINK DM IS He. What I think is it can be COMPARED TO IT with a different mass management.
imatfaal Posted February 26, 2015 Posted February 26, 2015 So it is assumed it is a high mass particle.Nope - it is assumed to have mass. That mass has to represent some sort of balance, as hydrogen and helium and every other element.What is this meant to mean? Because it is helium that stabilises inflation I believe it is an appropriate particle to approximate the DM particles properties against.The inflationary epoch was way way before Helium - before Hadrons, and even before Baryons The basic approach I have taken to defining this is to question whether it is a particle that reflects a helium particle with a high velocity.What? I do not automatically assume that DM is a helium particle travelling very fast.We know that DM is non-baryonic through our models of big-bang nucleosynthesis which is directly confirmed by the intensity and distribution of the CMBR. If it isn't baryonic then it definitely isn't He. By the way if it was travelling fast then it would impact interstellar dust and glow - it doesn't that is why it is dark
GeneralDadmission Posted February 26, 2015 Author Posted February 26, 2015 yup ok if you say so. Nobody has answered a single question I've asked with a "?" on it, only wanged on with objecting to the holes in my vocabulary. You guys should be ashamed of yourselves. You give the teaching trade a really bad look. -3
imatfaal Posted February 26, 2015 Posted February 26, 2015 yup ok if you say so. Nobody has answered a single question I've asked with a "?" on it, only wanged on with objecting to the holes in my vocabulary. You guys should be ashamed of yourselves. You give the teaching trade a really bad look. I presume you mean this What is the difference between an elements normal rest mass and the mass it accumulates as a result of acceleration? Did you not read this? ... For starters it is relative velocity not acceleration that in certain usages of mass will lead to a change...
Delta1212 Posted February 26, 2015 Posted February 26, 2015 yup ok if you say so. Nobody has answered a single question I've asked with a "?" on it, only wanged on with objecting to the holes in my vocabulary. You guys should be ashamed of yourselves. You give the teaching trade a really bad look. Two points: First, most of the people here aren't teachers. Second, and I'm not trying to be mean, but the holes in your vocabulary make most of your questions sound a bit like "What can I find purple monkey dishwasher?" And that is exceedingly hard to answer. No one here is trying to pick on what you said just for the sake of picking on you. They're trying to figure out what it is that you're actually trying to ask so that they can point you in the right direction. 2
studiot Posted February 26, 2015 Posted February 26, 2015 IMHO we are all being unfair to General Dadmission. The question posed is a very good one and as clear as the general physicists's answer, since physicists cannot agree amongst themselves as to the nature of mass. Just look here. http://en.wikipedia.org/wiki/Mass_in_general_relativity On the other hand, both sides of this discussion need to be even tempered for it to be fruitful. General Dadmission, if someone does not understand your words or finds them unclear, what is the practical way to proceed, since you are asking the question and presumably want the answer. I do not claim to be sufficiently well versed in modern and theortical physics to supply an answer but would like to set this in context. What I think you are asking about has puzzled physicists since Newton, who first realised that there are two effects in nature that we call mass. In Newton's day they reconciled Force = mass times acceleration and the the gravitational law. It is interesting that inertial mass and gravitational mass can be shown to be equivalent in classical systems, although it took approximately two hundred years to fully work this out. To put this in context, Physics has achieved several major successes in combining effects, once thought separate, the timescale in each case being one to two hundred years. For instance up to the 18th century they though heat and work were separate effects. Enough history. General Dadmission, I am wondering if your question is equivalent to Does the apparent increase in mass due to relativity show up as an increased gravitational force? Over to you for a fruitful and respectful discussion.
ajb Posted February 27, 2015 Posted February 27, 2015 yup ok if you say so. Nobody has answered a single question I've asked with a "?" on it, only wanged on with objecting to the holes in my vocabulary. You guys should be ashamed of yourselves. You give the teaching trade a really bad look. You need to ask clear questions if you hope to get any chance of a clear answer. You want to know the mass of dark matter. Well we don't know. However, there are several 'kinds' of dark matter; cold, warm and hot. Cold ~ few eV (eg lightest supersymmetric particle) Warm ~ 300 eV to 3000 eV Hot ~ GeV – TeV This just gives you the sort of masses one is talking about with the different 'kinds' of dark matter that could be allowed with current observations.
GeneralDadmission Posted February 27, 2015 Author Posted February 27, 2015 You need to ask clear questions if you hope to get any chance of a clear answer. You want to know the mass of dark matter. Well we don't know. However, there are several 'kinds' of dark matter; cold, warm and hot. Cold ~ few eV (eg lightest supersymmetric particle) Warm ~ 300 eV to 3000 eV Hot ~ GeV – TeV This just gives you the sort of masses one is talking about with the different 'kinds' of dark matter that could be allowed with current observations. That is super interesting. I just found that a particular model suggested variability in DM state. I think I'll be able to follow the equations when they get complex now. That is a great place to start.
ajb Posted February 27, 2015 Posted February 27, 2015 I just found that a particular model suggested variability in DM state. Can you provide a reference for us?
GeneralDadmission Posted February 27, 2015 Author Posted February 27, 2015 General Dadmission, I am wondering if your question is equivalent to Does the apparent increase in mass due to relativity show up as an increased gravitational force? Over to you for a fruitful and respectful discussion. That would be one question I can't say I've heard a direct answer on. It would be good to know the data now I have some idea what I'd be looking at with the particle. Thanks for your thoughts and consideration studiot. I don't think the way I was thinking about this question to begin with was the appropriate analysis I was looking to understand but I'll give it a little more thought.
robinpike Posted February 27, 2015 Posted February 27, 2015 General Dadmission, I am wondering if your question is equivalent to Does the apparent increase in mass due to relativity show up as an increased gravitational force? Over to you for a fruitful and respectful discussion. If relativistic mass showed up as an increased gravitational force, wouldn't that cause problems? With respect to our frame of reference, if there was a particle moving at almost the speed of light (the particle could be anywhere in the universe), then by the same token, that particle could consider us as moving at almost the speed of light - and our sun too. If relativistic mass increased gravitational force, then would it generate the bizarre situation where our sun is seen to have enough relativistic mass to become a black hole?
swansont Posted February 27, 2015 Posted February 27, 2015 If relativistic mass showed up as an increased gravitational force, wouldn't that cause problems? With respect to our frame of reference, if there was a particle moving at almost the speed of light (the particle could be anywhere in the universe), then by the same token, that particle could consider us as moving at almost the speed of light - and our sun too. If relativistic mass increased gravitational force, then would it generate the bizarre situation where our sun is seen to have enough relativistic mass to become a black hole? That's an argument for why the answer to the question is "no"
GeneralDadmission Posted February 27, 2015 Author Posted February 27, 2015 If relativistic mass showed up as an increased gravitational force, wouldn't that cause problems? With respect to our frame of reference, if there was a particle moving at almost the speed of light (the particle could be anywhere in the universe), then by the same token, that particle could consider us as moving at almost the speed of light - and our sun too. If relativistic mass increased gravitational force, then would it generate the bizarre situation where our sun is seen to have enough relativistic mass to become a black hole? I have to disagree with swansont. Gravitational force is associated to vacuum. DM has a -1 vacuum value and normal has a 1 value. I would assume that high velocity mass is an exaggeration of this dynamic so that the velocity gravitation force equates to positive vacuum force and the extra force of the massive body is neg-vacuum force. Possibly the other way round but I'd have to consider it further. Yes I would have to assume it is the other way around so that the massive body has the colder(lower EM) value.
imatfaal Posted February 27, 2015 Posted February 27, 2015 ! Moderator Note OK - this thread just got too silly. I am moving it to Speculations. Whilst asking questions about relativistic mass is exactly what this forum is for - the most recent posts by the OP have been so far from accepted physics (or even recognizable as science) that Speculations is the only possible home other than the trash-can. Either the thread can get back onto the topic of the slightly out-dated but mainstream concept of relativistic mass, or the OP can explain within the guidelines of the Speculations forum what his/her new ideas are, or the thread will be locked. GeneralDadmission - please note: the main fora are not suitable for you to expound your ideas in - anything that is not firmly founded in accepted science must be discussed only in the Speculations Forum.
swansont Posted February 27, 2015 Posted February 27, 2015 I have to disagree with swansont. Gravitational force is associated to vacuum. DM has a -1 vacuum value and normal has a 1 value. I would assume that high velocity mass is an exaggeration of this dynamic so that the velocity gravitation force equates to positive vacuum force and the extra force of the massive body is neg-vacuum force. Possibly the other way round but I'd have to consider it further.Yes I would have to assume it is the other way around so that the massive body has the colder(lower EM) value. What's your evidence, and/or model? How is any of this testable?
GeneralDadmission Posted February 28, 2015 Author Posted February 28, 2015 (edited) What's your evidence, and/or model? How is any of this testable? I should I just make assumptions from here and not ask questions? I'm trying to identify which particular maths is used for vacuum I guess. Isotopic balance(which particles are stable) is regulated by vacuum isn't it? If helium 4 represents the particle that would require the least energy to accelerate to c, I would measure how much energy that would reguire to begin with. Edited February 28, 2015 by GeneralDadmission
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