<div dir="auto"><div>Tom,</div><div dir="auto"><br></div><div dir="auto">Yes, I used my language very carefully that is why I used the phrase <b>effectively</b> at rest. So please ponder over the following reasoning, :</div><div dir="auto"><br></div><div dir="auto"><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt;text-align:justify"><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline">Newton Law of Inertia states that “An object shall continue to be in </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">state of rest</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline"> or </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">state of motion with constant velocity</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline"> unless acted upon by a Force. This is a very powerful statement indicating some equivalence between </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">state of mass particles</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline"> at </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">rest</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline"> or </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">state of motion with constant velocity</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline">, which leads us to two possible interpretation:</span></p><br><ol style="margin-top:0pt;margin-bottom:0pt"><li dir="ltr" style="list-style-type:decimal;font-size:11pt;font-family:arial;vertical-align:baseline"><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt;text-align:justify"><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline">The term </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">state</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline"> is characterized by some property, perhaps geometrical property, of mass particles which is unchanging at constant velocity.</span></p></li><li dir="ltr" style="list-style-type:decimal;font-size:11pt;font-family:arial;vertical-align:baseline"><p dir="ltr" style="line-height:1.2;margin-top:0pt;margin-bottom:0pt;text-align:justify"><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline">Even the apparent </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">state of rest</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline"> is in some sense a state of </span><span style="font-size:11pt;font-family:"pt sans narrow";font-weight:700;vertical-align:baseline">motion with constant velocity</span><span style="font-size:11pt;font-family:"pt sans narrow";vertical-align:baseline">.</span></p></li></ol><div class="gmail_extra" dir="auto"><br><div class="gmail_quote" dir="auto">So once you will have time, you may provide your feedback on <span style="font-size:14.6667px;font-family:arial"> "</span><span style="font-family:arial;font-size:14.6667px;line-height:20.24px">So the important point here is the variance..." </span>and on above reasoning, to possibly explore together the notions of "<b>Rest Velocity" </b>and<b> "Moving State of Rest" </b></div><div class="gmail_quote" dir="auto"><br></div><div class="gmail_quote" dir="auto">By the way, I mostly agree with your following statements:</div><div class="gmail_quote" dir="auto"><span style="font-family:arial;font-size:14.6667px"><br></span></div><div class="gmail_quote" dir="auto"><span style="font-family:arial;font-size:14.6667px">Your reference to stronger gravity slowing down time is incorrect. It is the atomic clock which has slowed down, not time. If you use a pendulum clock, you will find that "time" speeds up with stronger gravity. Gravity affects both clocks, but in opposite sense, yet relativists acknowledge the one, but not the other. This is inconsistent.</span><br></div><div class="gmail_quote" dir="auto"><br></div><div class="gmail_quote" dir="auto">And then in a separate email Mike mentioned that background is both like something and like nothing. Is it something like this:</div><div class="gmail_quote" dir="auto"><br></div><div class="gmail_quote" dir="auto">(1/2) +(-1/2) = 0 = Nothing</div><div class="gmail_quote" dir="auto"><br></div><div class="gmail_quote" dir="auto"><span style="font-family:sans-serif">|1/2| +|-1/2| = 1 = Something</span></div><div class="gmail_quote" dir="auto"><span style="font-family:sans-serif"><br></span></div><div class="gmail_quote" dir="auto"><span style="font-family:sans-serif">Regards,</span></div><div class="gmail_quote" dir="auto"><span style="font-family:sans-serif"><br></span></div><div class="gmail_quote" dir="auto"><span style="font-family:sans-serif">Tufail Abbas</span></div><div class="gmail_quote" dir="auto"><br></div><div class="gmail_quote">On Jun 12, 2017 10:46 PM, "<a href="mailto:carmam@tiscali.co.uk">carmam@tiscali.co.uk</a>" <<a href="mailto:carmam@tiscali.co.uk">carmam@tiscali.co.uk</a>> wrote:<br type="attribution"><blockquote class="quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div><span style="font-size:11pt;font-family:arial;vertical-align:baseline">Tuffail, you said : "Source and receiver made of matter are both </span><span style="font-size:11pt;font-family:arial;font-weight:700;vertical-align:baseline">effectively at rest</span><span style="font-size:11pt;font-family:arial;vertical-align:baseline"> wrt background medium." This is definitely not correct. If they are both at rest WRT the background medium, they must both be at rest WRT each other. I am assuming here that you mean that the background medium is one contiguous medium moving as one between source and receiver, and that is a very unusual circumstance, which is not true in general. Each star system the light passes will have its own speed and its own entrained medium. The system could have any velocity and any direction, as will the medium. Then there is interstellar gas, which also could be moving in any direction and with any velocity.</span></div><div><span style="font-size:11pt;font-family:arial;vertical-align:baseline">What does effectively mean?</span></div><div><span style="font-size:14.6667px;font-family:arial">Your paragraph starting "</span><span style="font-family:arial;font-size:14.6667px;line-height:20.24px">So the important point here is the variance..." needs more time to evaluate than I have right now, so will have to wait.</span></div><div><span style="font-size:14.6667px;font-family:arial"><span style="line-height:20.24px">Your reference to stronger gravity slowing down time is incorrect. It is the atomic clock which has slowed down, not time. If you use a pendulum clock, you will find that "time" speeds up with stronger gravity. Gravity affects both clocks, but in opposite sense, yet relativists acknowledge the one, but not the other. This is inconsistent.</span></span></div><div><div class="quoted-text"><span style="font-size:14.6667px;font-family:arial"><span style="line-height:20.24px">Tom Hollings.<br></span></span>
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----Original Message----<br>
From: <a href="mailto:tufail.abbas@gmail.com" target="_blank">tufail.abbas@gmail.com</a><br></div><div class="quoted-text">
Date: 11/06/2017 20:57<br>
To: <<a href="mailto:carmam@tiscali.co.uk" target="_blank">carmam@tiscali.co.uk</a>>, "General Physics and Natural Philosophy discussion list"<<a href="mailto:physics@tuks.nl" target="_blank">physics@tuks.nl</a>><br>
Subj: Re: Constant light speed<br>
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<div dir="auto"><div dir="auto"><br></div><div dir="auto"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">Tom, </span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline"><br></span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">Off-course, meaning of constancy speed of light is not so straightforward. </span></p><br><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">Constant speed of light has its roots in Maxwell equations, which is inverse of c squared is equal to product of permittivity and permeability. If c is variable then permeability and permittivity should also vary. Before we declare that speed of light is not constant, we need a consistent explanation along with implication of this variability of c over permittivity and permeability. Assuming that we do not have a </span><span style="font-family:arial;font-size:11pt">consistent explanation (or if you have then please share), we can only discuss the meaning of this constant speed, and in this context di-sitter experiment seems to be meaningful. Where we discuss velocity the first question that is obvious is with respect to what. And here are some statements trying to find the answer to this question, to which I have commented below:</span></p><br><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline;color:rgb(33,150,243)">>>>>But if light is a constant WRT the medium or the gravitational field of any nearby object, then the two stars would be seen in their "correct" places at all times.</span></p><br><br><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">So speed of light is constant wrt medium( which is different from gravitational field as per my point of view). Source and receiver made of matter are both </span><span style="font-size:11pt;font-family:arial;font-weight:700;vertical-align:baseline">effectively at rest</span><span style="font-size:11pt;font-family:arial;vertical-align:baseline"> wrt background medium. This perfectly explains the constancy. Speed of A(matter) wrt B(medium) is zero, speed of C(light) wrt B is c. Hence speed of A wrt C is also c. I agree that this bizarre </span><span style="font-size:11pt;font-family:arial;font-weight:700;vertical-align:baseline">effective rest</span><span style="font-size:11pt;font-family:arial;vertical-align:baseline"> , needs a physical explanation. But definitely an intuitive explanation exists for such a bizarre state of rest, despite the relative velocity of motion.</span></p><br><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline;color:rgb(33,150,243)">>>>>The beam from the moving laser strikes the glass at a higher velocity and its light waves will appear to have a frequency 10% higher. This frequency will be preserved throughout the process. And the observer will see the moving laser beam as having a higher frequency – a Doppler shift! But the final velocity of both beams will be the same: c.</span></p><br><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">So the important point here is the variance of frewuency or energy content per unit time. Let me try to explain, how this could happen. Let the source(star) emits a </span><span style="font-size:11pt;font-family:arial;font-weight:700;vertical-align:baseline">constant amount of energy per unit area per unit time t’,</span><span style="font-size:11pt;font-family:arial;vertical-align:baseline"> which is constant for all source, irrespective of the </span><span style="font-size:11pt;font-family:arial;font-weight:700;vertical-align:baseline">observed frequency</span><span style="font-size:11pt;font-family:arial;vertical-align:baseline"> . Instead of thinking of Doppler Effect to possibly change the relative travelling speed similar to the case of sound waves, here the source can be modelled as emitting photons consisting of sub-energy packets. All energy sub-packets are released wrt medium at the instanraneous position of source. So if the source is moving away, then number of energy sub-packets travelling per unit length toward the receiver will reduce. These energy sub-packets will be received by source into a packet of single photon collected over a constant period of time t’. Time frequency 1/t’ of all photons is same. What we see in equation hf, is measure of space frequency. Long ago I answered this question on Quora. </span></p><br><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><a href="https://www.quora.com/Why-does-a-strong-gravity-slow-down-time/answer/Tufail-Abbas-1" style="text-decoration-line:none" target="_blank"><span style="font-size:11pt;font-family:arial;color:rgb(17,85,204);text-decoration-line:underline;vertical-align:baseline">https://www.quora.com/Why-<wbr>does-a-strong-gravity-slow-<wbr>down-time/answer/Tufail-Abbas-<wbr>1</span></a></p><br><br><span style="font-size:11pt;font-family:arial;vertical-align:baseline">The answer though is not accurate but it only draws analogies, so not to be taken too literally, but it gives an idea about what I am saying about sub-packets. If the logic seems plausible or otherwise if </span><span style="font-family:arial;font-size:11pt">it create more doubts , then please provide feedback</span></div><div dir="auto"><span style="font-size:11pt;font-family:arial;vertical-align:baseline"><br></span></div><div dir="auto"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">Regards,</span></div><div dir="auto"><br></div><div dir="auto"><span style="font-size:11pt;font-family:arial;vertical-align:baseline">Tufail</span></div><div><br><div class="gmail_extra"><br><div class="gmail_quote"><br></div></div></div></div>
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