studiot

As required by the Modulator I have started a new thread for you in Speculations. This is blatantly untrue as I specifically requested this one hour previously. Which is why I am asking you to explain and define the three terms, I have underlined below, you have introduced that I (and probably many others here) are not familiar with. In particular the re-propulsion idea. Are you, for instance, proposing that the same photon is emitted or what after a photo-atomic and photo-electron event ? I think Marcus is referring to change of propagation conditions and Wiki is referring to constant or unchanging propagating conditions, in respect of the constancy of the speed of light. So here is your opportunity to set the record straight.

Once again there are many pithy comments in your posts in this thread Eise. +1

Which is why I am asking you to explain and define the three terms, I have underlined below, you have introduced that I (and probably many others here) are not familiar with. In particular the re-propulsion idea. Are you, for instance, proposing that the same photon is emitted or what after a photo-atomic and photo-electron event ? I think Marcus is referring to change of propagation conditions and Wiki is referring to constant or unchanging propagating conditions, in respect of the constancy of the speed of light.

You need to do more than nod wisely when someone tells you something. Your responses tell me that you are not understanding what we are telling you. I am not saying this to be nasty, but because you need to think before you answer. In particular you need to answer the questions we are asking, they are all meant to help. You are not doing this at the moment.

You need to show you understand more basic algebra before tackling the next stage. Did you do the algebraic comparison I suggested or just guess? A semicirircle does not have a single equation. It is described by the intersection of a circle and a straight line along with some conditions.

You don't need trigonometry to obtain this standard result, just good old Pythagoras.

That's the same thing.

Derive from what? Another way to view this equation is (x - f)2 +(y - g)2 = r2 This give a circle, centre (f, g) radius r. Multiply it out and compare.

The direct self- contradiction is shown in bold. Then you will be able to post the derivation - it's time to put up or shut up. The frequency that any clock ticks at in its own or any other frame is irrelevant to what is read on that clock by any observer. Every observer will make an identical sequence of readings of the clock say 1,2,3,4, because that is the nature of your digital clock and it can only show this sequence. They will, however, differ in the readings on their own clocks that coincide with each number on the broadcasting clock. This correspondence will depend upon two factors viz their own velocity relative to the broadcasting clock and also the time lag between when the broadcasting clock face shows say 4 and when the observer reads the clock face as showing 4. This time lag will increase as the outward journey progresses and decrease during the return. And yes, during this sequence of observations, the colour of the numbers on the clock face will change for the observer due to the Doppler shift. But these colours are irrelevant to the number displayed. As I said the only way to observe or see the broadcasting clock 'running slow' is to compare the readings broadcast in whatever colour, with the readings made on an identical clock carried along on the journey. This would occur naturally anyway as the separation, and thus the time lag, increases.

I am at a complete loss to understand where you are coming from in this thread. You correctly state Einsteinian relativistic formulae about time (saying they are relativistic) and then ask questions about frequency. You then directly contradict yourself by saying the formulae are 'classical'., but do not say why. I don't know what you mean by 'classical' since modern Physics regards Einsteinian relativity as classical, but no matter I assume that since you wish to make a distinction you mean theory preceding this. So far as I am aware c and square roots do not enter into any preceding theory. I assume you know the correct classical formulae, but we can discuss them if you wish and compare them with the Einsteinian ones. You are also wrong to say that no one has offered you the correct changes of frequency for the relative speed you specified. These appeared in my post that you quoted. Finally I asked you simple question more than once. But each time I have received no answer. What does the frequency either perceived or as generated) have to do with the reading on the clock?

Substances (AKA matter) can come in three forms Elements The smallest particles of these are called atoms and cannot be broken down into smaller particles of substance. The particles of each element are chenically the same as each other but different from the particles of any other element. There are around 150 elements known. Compounds. Two or more atoms of the same or different elements can combine chemically, which means they act as one unit to form molecules. These are called compund substances or just compounds. The molecules are thus the smallest particle of compound substances. All the molecules of a given compound have the same combination of atoms. Mixtures are just what is implied. A collection of molecules of different compounds and/or elements that are not chemically bound together. Does this help?

I should clarify this line to read that nu nought is the original frequency and nu is the observed frequency.

Give the man a green star then here I will do it for you. +1 sensei

Even though you have failed to answer my questions. You have chosen a relative velocity of u = 0.6c The relativistic doppler shift for two bodies moving with an inline relativistic velocity is given by [math]\frac{\nu }{{{\nu _0}}} = \frac{{\sqrt {1 - \frac{{{u^2}}}{{{c^2}}}} }}{{1 + \frac{u}{c}}}[/math] Where the observed frequency is [math]\nu [/math] and the shifted frequency is [math]{{\nu _0}}[/math] and u is the inline relative velocity. Which I make half and double the original frequencies (no doubt why you chose that value for u). So what effect does that have on the observed reading on the clocks as tabulated?

The whole matter is neither clearly nor unambiguously explained by yourself., though Janus has added further meat to his bone for your benefit. Start with a very simple example that has nothing to do with 'relativity'. Take a clock with hands and an observer that views the clock via a mirror. The observer will directly see the clock running backwards (anticlockwise). So he makes a (perhaps mental) adjustment to the reading to compensate so that he can consider (the posh Physics term is transform) what he actually sees to his own form of reckoning. In the same way the travelling observer directly sees a clock fact that is acting differently from his own clock, but in your case he is monitoring the changing of the numbers. So, like any good Scientist, he records his readings. He will have a table with readings on his clock in one column and tabulated against each entry he will have another reading of what he notes on the Earth clock, which will generally be different. So your first task is to make clear in which system are we reckoning time? Because he will need a third column transforming the readings in either the first or second column to the other system as they are not directly comparable. This would be true in both Galilean and Einstinian relativity as there will alway be a time lag between the Earth clock display and the traveller reading. Further this delay will be a function of time or separation and not constant.

Having received the book I can now definitely recommend it. However the proviso that you need a bit more than just just algebra definitely stands. Experts often overlook just how much subject lore they use unconsciously. It is also refreshing to see such an offerening from a small independent publisher, and at such a reasonable price.

The post you replied to doesn't belong here but here There was some kind of screw up in the system last night. I blame Trump.

Here is a plot (courtesy Lawden) of the Friedmann solutions to the Einstein Field equations showing the time evolution of universes with different input cosmological constant (k) With negative k the universe expands without bound With zero k the universe becoems asymptotic. With positive k the universe expans and contracts cyclically. So the real question is not Is the uninverse infinite, but Will the universe ever be infinite, and if so when?

Every time the gas heater fires up there is a flow of wasted gas until everything settles down to running conditions. This is the same as the fuel used when cold starting a standard car is equivalent to consumption in the 5 - 15 mpg range. In heating terms the phenomenon is known as boiler cycling (which you don't want) So there is a trade off between tight control and lots of small inputs which waste fire up fuel and longer bursts which overheat more. One solution is an intermediate buffer heat store.

I think it is the sheer two-facedness (Sorry Janus I like your posts really) of the heirarchy, in not practicising what they preace to the lower ranks about how people 'should' behave that turns many off religion. They suffer no 'dissonance' at all , they just don't like being lied to.

Yes I also wondered that.

I wonder if this was a reply to my question, since your assertion shows a misunderstanding of the basics of Physics. Energy and Force are different things. If you sit on a chair (and don't fall off ) There is no involvement of Energy whatsoever. Yet there is a balance of opposing forces countering each other. It take no energy to generate a force. Energy becomes involved when that force moves something. Before tackling your more detailed/advanced questions you need to understand the meaning of these fundamental words or you will not progress. Do you need more detailed explanation?

I don't know why you seem determined to change the OP, which was Is there a ratioanl reason for religion? Neither Faith nor Logic were mentioned. So in short, yes there is a rational reason for religion because Religion offers a harmonius code of conduct and a sufficient proportion of religous people live their lives in this way. That is not to say that there are not disharmonius religous people or disagreable aspect of religion. That is a rational reason but not a logical one. Given the premise that religion leads to harmonius people a logical 'conclusion' (as you put it) would be that there is a reason for religion. I don't know if you can see the differences in the two statements.

Good Feynman quote, Pavel. +1

Wow, you never know when you wake up and log on to SF what new things you might learn. Thank you for fonding that Eise +1 I have never heard of absement and I couldn't think of a use for the second (or even third fourth etc) integral. If we take the velocity as some function of t and integrate it we indeed get the distance travelled (but not necessarily the displacement) To get the second integral we obviously integrate again with respect to t. I will take the example that v = f(t) = v1 (a constant) to work from. More complicated functions will necessarily lead to more complicated integrals. So generally [math]I = \int {f\left( t \right)dt} = \int {vdt} [/math] performing the integration yields [math]{I_1} = \int {{v_1}dt} = {v_1}t + C[/math] performing the second integration yields [math]{I_2} = \int {\left( {{v_1}t + C} \right)dt} = \frac{{{{\left( {{v_1}} \right)}^2}}}{2} + Ct + D[/math]