tag:blogger.com,1999:blog-6654521948166449826.post2830033315177845783..comments2021-08-19T18:10:35.129+01:00Comments on n0b0dy0fn0te: You Must Be Off Your Brane!Doc hackenslashhttp://www.blogger.com/profile/10835343955496184376noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-6654521948166449826.post-10744021857492526262016-04-07T16:12:29.516+01:002016-04-07T16:12:29.516+01:00I should have said causation not correlation. I ha...I should have said causation not correlation. I have the Gleick but have not yet read it. I did not want to buy it initially because I thought it too slim given the subject matter. But after you raved about it that persuaded me to purchase it. Though the book I would love to get is Never At Rest by Robert Westfall which is regarded as the definitive Newton biography. I think however it is out of print which is somewhat surprising. Amazon have it on kindle but as I only buy physical books that is not much use to mesurreptitious57https://www.blogger.com/profile/09536010190276530579noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-70128330109916818202016-04-07T14:34:46.410+01:002016-04-07T14:34:46.410+01:00I wouldn't even say there is a correlation (re...I wouldn't even say there is a correlation (remember that correlation is not causation), the colour emitted by a photon is a direct result of its wavelength. <br /><br />As for Newton, I recommend the biography of him by James Gleick. Doc hackenslashhttps://www.blogger.com/profile/10835343955496184376noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-82922508119446419222016-04-07T14:20:41.160+01:002016-04-07T14:20:41.160+01:00So there is a direct correlation between the wavel...So there is a direct correlation between the wavelength of a photon and the colour it emits. This is evidence that light is not one colour but many namely red / orange / yellow / green / blue / indigo / violet as they appear on the electromagnetic spectrum of visible light. Although it was Newton who discovered this not Einstein when he split light up into its constituent parts by passing it through two prisms. This was after he pushed a bodkin into his own eye to see the effect more close up. Before then light was thought to only be white and nothing else surreptitious57https://www.blogger.com/profile/09536010190276530579noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-61631225888435631012016-04-06T10:30:27.470+01:002016-04-06T10:30:27.470+01:00I've made a crude animation and tagged it to t...I've made a crude animation and tagged it to the end of the post illustrating what I was talking about here.Doc hackenslashhttps://www.blogger.com/profile/10835343955496184376noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-6928472385758526312016-04-05T15:45:43.906+01:002016-04-05T15:45:43.906+01:00This comment has been removed by the author.Doc hackenslashhttps://www.blogger.com/profile/10835343955496184376noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-55309672867307241602016-04-05T15:32:04.342+01:002016-04-05T15:32:04.342+01:00OK, had a think about this, and I think I can clea...OK, had a think about this, and I think I can clear it up without a new post. I did try to make an animation showing this, but it turned out to be problematic on my archaic laptop.<br /><br />It's slightly misleading to think of the energy level of a photon as varying according to its wavelength (there's another problem with the way that you've expressed that, which reveals an erroneous understanding, but I'll come back to that shortly), the way you should think of it is as the energy and the wavelength being essentially the same thing. <br /><br />The way you've expressed it above, as 'a particle that can travel indefinitely in a vacuum at c with no deviation from that' reveals that you're thinking slightly askew about the relationship. Light always travels at <i>c</i> in a vacuum, with no deviation, but the wavelength can vary hugely. I t most certainly does apply to visible light (which is no different to the rest of the electromagnetic spectrum, except that it's the frequency range that the opsins in our eyes respond to; as always, we have to be aware that light is a bit of a red herring here, being no more nor less than the thing we're aware of and can point to that propagates at <i>c</i>).<br /><br />Have a look at the waves in the images above dealing with QM. All those images are the same dimensions, which makes life easier. You can actually think of those waves as moving at the same speed, but with different wavelengths, thus the top image, showing one complete wave-cycle, is travelling at exactly the same speed as all the other images. If you think of that image as passing an imaginary vertical line at the right-hand end of the image in a specific amount of time, and the other images doing exactly the same, and in the same amount of time, you can see how the speed of light can remain the same while the frequency varies. The other images are covering exactly the same distance in both space and time, but the time between peaks varies. Hope that clears that up.<br /><br />Incidentally, your comment 'I also know that most wavelengths are relatively tiny apart from radio waves whose wavelengths can be measured in kilometres as opposed to most other electromagnetic phenomena whose wavelengths can be measured in millimetres' is incorrect. The electromagnetic spectrum covers the entire range of frequencies. Indeed, you can see the variation in visible light quite easily, because that's what we see as colour.Doc hackenslashhttps://www.blogger.com/profile/10835343955496184376noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-17662755437164587852016-04-05T14:31:05.640+01:002016-04-05T14:31:05.640+01:00Is it known if the gravitational waves that were d...Is it known if the gravitational waves that were detected last year and confirmed this year were red shifted or blue shifted? Even if it is would it be of any use in falsifying or confirming the brane hypothesis? Since the black holes they originated from were only 1.3 billion light years away which is nowhere near the Cosmic Microwave Background Radiation which occurred just 380 000 years after the Big Bang surreptitious57https://www.blogger.com/profile/09536010190276530579noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-24815974558185797772016-04-05T12:28:33.388+01:002016-04-05T12:28:33.388+01:00I did not know that the energy level of a photon v...I did not know that the energy level of a photon varies according to its wavelength. I simply thought of it as a particle that can travel indefinitely in a vacuum at c with no deviation from that. Though I do know that wavelengths vary but just did not think this applied to visible light. I also know that most wavelengths are relatively tiny apart from radio waves whose wavelengths can be measured in kilometres as opposed to most other electromagnetic phenomena whose wavelengths can be measured in millimetres. I wonder if there is a reason for such a discrepancy surreptitious57https://www.blogger.com/profile/09536010190276530579noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-28133872250119593622016-04-05T11:56:12.423+01:002016-04-05T11:56:12.423+01:00Some misconceptions there. Firstly, nobody's e...Some misconceptions there. Firstly, nobody's ever detected a string (if they had, all the objections to string theory would evaporate). Secondly, we can't currently probe to anything like the Planck length. Thirdly, photons don't have zero mass, they have zero <i>rest mass</i>, and this is important. Their mass is associated with their motion. You can think of it loosely like kinetic energy - although, if you run too far with this, it gets misleading very quickly.<br /><br />There's a clear correlation between energy and distance. This is fairly obvious if you think carefully about it. Think about one of those pinart toys, in which you impress your face into the pins on one side and an image appears on the other. The resolution attainable is directly related to the size of the pins. Now try to imagine probing one of these for structure, first by throwing tennis balls at it and recording the rebounds. You're not going to measure an awful lot of structure in there unless the size of the pins is comparable to that of the tennis balls. Now try some ping-pong balls, and you'll find that a little more structure is revealed, though not a huge amount. Now try again, this time with small ball bearings. Each time, the ball you're throwing at the pinart toy is smaller, until you get to the scale of the pins, at which point you get exactly the same resolution as you have in the toy. Go smaller still, and you'll even be able to discern the curvature on the top of each pin.<br /><br />No we can move on to looking at smaller and smaller objects by the same method. There's an inverse relationship between energy and distance when we're talking about, for example, photons. Lower energy photons have longer wavelengths (infrared, etc), while higher energy photons have shorter wavelengths (x-rays, etc). This energy relationship is most directly expressed in quantum mechanics, in which the Planck scale measures are made concrete. You're aware, for example, that the Planck length (1.616 x 10^-35 metres) and the Planck time (5.391 x 10^-44 seconds) are both tiny, while the Planck mass is huge (2.176 x 10^-8 kg, compared to the proton mass at 1.673 x 10-27 kg). This is a direct result of the energy/distance relationship.<br /><br />QM also tells us that the same relationships that hold with photons also hold for other particles thus, even when we're using electrons, lead ions, or whatever in our particle accelerators (we tend to use charged particles because they're much easier to accelerate, using magnets), the same energy/scale relationship holds. Thus, accelerating to higher energies in our particle accelerators effectively increases resolution, just as in the pinart example above.<br /><br />Finally, the limitation at the Planck length isn't based on something we've detected, it's rooted in considerations of what happens to our physical theories when we start to get below that scale, namely that the solutions to our equations tend to infinity, meaning that it's unclear whether it's possible to glean any information from below that scale, or indeed whether any questions concerning such scales are even meaningful or coherent.<br /><br />Ultimately, the questions rely on an intuitional approach to the topic that we're fully aware simply doesn't apply to this subject matter. It's middle-world thinking.Doc hackenslashhttps://www.blogger.com/profile/10835343955496184376noreply@blogger.comtag:blogger.com,1999:blog-6654521948166449826.post-46880221727798448232016-04-05T08:15:06.179+01:002016-04-05T08:15:06.179+01:00Particles have mass which corresponds to their ene...Particles have mass which corresponds to their energy which is the frequency at which their respective strings vibrate. But what about massless particles like photons? Are they also made of strings? And if they are how can their frequency be measured when they have zero mass? A string has a minimum length which is the Planck length. But as that is the smallest detectable measurement currently possible could there be strings smaller than that which cannot be detected at this point in time? And as the Planck length is the smallest measurement currently possible then something that small can presumably be measured without necessarily having to build a collider the size of the solar system to measure it nowsurreptitious57https://www.blogger.com/profile/09536010190276530579noreply@blogger.com