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If you think being 13.8 billion years old is "fresh and new", you have a curious conception of these terms.

Any sudden movement will disturb the adjacent air. In both the cases you mention there is a stretching action followed a break in quick succession. When the break occurs, the stored energy in the stretch is released suddenly, causing a very tiny but rapid movement of a portion of the paper or tape. This will create a sound wave. There does not have to be - and in this case there won't be - a vibration, just a single motion. This is shown in fact by the absence of any discernible pitch or tone to the sound. It's more or less white noise. If there were vibration, that would cause a sound at a particular pitch, or pitches.

Speculation: So one thing I observe is that everything is so "fresh and new". We are not hampered by anything from the past. This makes sense as according to modern theory everything came from an "infinite point" and evolved over billions of years. So in effect this is a new "time". The question is were there any previous "times". According to Roger Penrose (scientist), this universe is born from the collapse of a previous one. In effect there is an eternal cycle of expansion and contraction. The question is were there were any "earth worlds" previously in time? And if so were they more connected to that of previous times? For us we are not connected to previous time at all. We obviously inherit the previous history of this world through ancient monuments and written history and cave drawings. But we have no link per se to time previous to the formation of this world. And hence the search and theorizing about what did actually happen. Eg there were quarks and other subatomic particles per se. The theory is that this universe is a "rehash" of the "smashup" of previous times. Essentially like a "recycle garbage bin" in time. Yet we see ourselves as completely new. Wonderous, exciting etc. The theory is that previous times are reflected very well in this world. Through our stories, creativity, art etc. The theory is that there is no such thing as "creativity". Our minds are drawing upon a "mashup" of the past !!!

Hello, I had a hiccup in explaining how sound is produced when materials break down. For example, A) we are tearing paper, B) we're unwinding duct tape. There is a break in the adhesion bonds. The breakage results in a sudden release of energy, which is converted to kinetic energy in some way, creating sound. How does sound occur? What's vibrating in there to cause it? I'm interested in physical part of production of sound in these processes.

Hi About 5 years ago, i think it was a morning, I was walking on a small countryside road in north of France Then I looked on the side and I saw the moon being very huge compared to usually It scared me, i think it looked about twice the size as usual I don't remember well, I took no photo, I think the size decreased pretty quickly, i don't remember well Would someone have an explanation/assumption/idea about this? Could that have been some reflect/visual effect? I think it was during a cold season Regards

All of the data analysis stuff in Python begins with the numpy library. Use numpy.mean() and numpy.median() after casting your list to a numpy.array like so: Data = numpy.array([1,2,3]) Honestly the best advice though is use chatGPT for little coding questions like this.

OP sounds a bit like an AI, but it’s a cool speculative post. To Mordred, the challenges of defining consciousness seem insurmountable, but when you have this requirement that something be conscious of something else, it has a unique signature in terms of correlations, optic nerve signals being correlated with external lights, etc. No different with AIs. It’s just a base level: you can’t say this creates consciousness, but you can say without it there is none. Anyway these correlative relationships may turn out interesting for studying physical systems. The smart money is against anthrocentist notions, including the specialness of our minds.

Radio works at the speed of light. Lasers are also already used for some communication. No time travel involved. Edit: my comment above was posted before the message above was seen. What do you mean by "binary light frequency"? And, it's still not clear why you think/thought information would be received before it is sent.

Thanks for the great replies I actually just asked the same question on LBC radio and the presenter read it out and amazingly someone replied via the radio station having calculated how long it would take the laser to return to earth. I actually thought that if we sent binary light frequencies to a reflector deep in space via laser that the information could be received before the information was sent.

No

You’re not wrong. I, in fact, paused with a similar self-critique when typing it. I think where maybe I landed after chewing upon it momentarily was how assigning capitalism as a root cause for our mediocre milquetoast attempts at mitigating climate change thus far is both a) too simplistic, and b) too convenient a scapegoat to emotionally let ourselves as individuals off the hook. Perhaps a better root cause of our Fiddling_Nero-level lethargy on climate gets framed as a sort of selfish shortsightedness; a desire for relief in the present moment at the expense of some still unrealized potential future narrative. At the risk of being reductive: Capitalism isn’t the root cause of anything, really. Dopamine and how we each act to spike it is. That won’t change by switching the social order to a more socialistic or even communistic one, though would certainly be helpful if we could all just be a little less horrible to each other and think a bit more about what’s left when we’re gone.

What is it in your scenario is it that makes you believe information might be 'time traveling'? Is it because you use lasers? Or because of the speed of light? Because it is 'round trip' travel? Because there is something about Mars that is special?

That would be a causality violation c is the speed limit of information exchange as well.

If we reflected lasers back to earth from mars could we receive information before the information is sent? If the information travelled at the speed of light to mars and back to earth would it effectively be time travel for information?

found it I finally recalled it was a series of Black star research "Irreversible gravitational collapse: black stars or black holes?" https://arxiv.org/abs/1105.3394 I certainly wouldn't argue with this. LOL I know any personal modelling I do I set Planck units as a constraint on anything involving spacetime or other fields. Funny thing is that boundary works well with the FLRW metric for the 10^{-43} second boundary the average estimated temp of 10^19 GeV when you convert is in the same orders of magnitude as Planck temperature. With the temperature scale factor relation. Blackbody temp can be estimated by the inverse of the scale factor. This also corresponds to 1 Planck length. just an interesting tidbit on last.

One problem I have with the central singularity. What happens when you apply Heisenberg's Uncertainty Principle to the singular event ( whether spatial or temporal singularity )? An exact location would mean indeterminate, even infinite, momentum, while an exact time would mean indeterminate, even infinite, energy. How would a particle, localized in such a way, remain trapped within the Event Horizon ? Now make that argument for all particles ingested by the BH and you have a BH which cannot exist. IOW, the singularity renders the theory inconsistent; either a singularity cannot exist, or Black Holes cannot exist. Yet we have photographic evidence of Black Holes, so where does that leave us ? I would be interested in a link to this article also. I'm interested in the proposed method ( pressure or force ) used to resist gravitational collapse at this radius.

It was several peer reviewed article on Arxiv but it was a few years ago that I followed the research and some of the proposed tests. However I'll take a look and if I can find the papers. If I can I'll post it. Point of detail the singularity conditions regarding the EH involve infinite redshifts and subsequent time dilation relations involving the EH. These conditions are the ones directly involved with regards to Hawking radiation. This also involves Unruh radiation https://arxiv.org/abs/0710.5373

I like indulging nice guys, Moon, so I'll start us off. Consider a constant acceleration ship, say 1g, for the confort of the occupants. "From the planetary frame of reference, the ship's speed will appear to be limited by the speed of light — it can approach the speed of light, but never reach it. If a ship is using 1 g constant acceleration, it will appear to get near the speed of light in about a year, and have traveled about half a light year in distance. For the middle of the journey the ship's speed will be roughly the speed of light, and it will slow down again to zero over a year at the end of the journey. As a rule of thumb, for a constant acceleration at 1 g (Earth gravity), the journey time, as measured on Earth, will be the distance in light years to the destination, plus 1 year. This rule of thumb will give answers that are slightly shorter than the exact calculated answer, but reasonably accurate." From Space travel under constant acceleration - Wikipedia We can then make other quick estimates to travel time "From the frame of reference of those on the ship the acceleration will not change as the journey goes on. Instead the planetary reference frame will look more and more relativistic. This means that for voyagers on the ship the journey will appear to be much shorter than what planetary observers see. At a constant acceleration of 1 g, a rocket could travel the diameter of our galaxy in about 12 years ship time, and about 113,000 years planetary time. If the last half of the trip involves deceleration at 1 g, the trip would take about 24 years. If the trip is merely to the nearest star, with deceleration the last half of the way, it would take 3.6 years." Now you might say"That's not too bad.". Only 113 000years pass on their home world to send a ship 100 000 light years. And a relatively short time to send it to a nearby star. Even doubling that time for two-way journey seems reasonable. Now comes the hard part. ( and I'm not going to attempt to quickly find/perform the calculation; I'll leave it to better, more fastidious, minds than mine ) How much Hydrogen do you need to carry, or collect along the way, in order to sustain a fusion reaction capable of sustaining a constant 1g acceleration/deceleration ?

The collapsing star is a dynamic state, and quite different from a free-falling object. There's dense stuff, and then not even Pauli-exclusion can support it. OK, so there's even more squish, at least at first. A spatial dimension rotates and is replaced by time, and that time dimension is bounded. What was the time dimension rotates out to a spatial one, one with nearly infinite extension at that. Lots of new room to spread out, but the causal light cones don't allow arbitrary travel down this big space, so I cannot say the compression ends. An example of the space available inside a black hole, Sgr-A and the black hole at the center of Andromeda share a common singularity. They're the same black hole, a region of 4D spacetime bounded by a 3D event horizon hypersurface, and in that case, the same (connected) hypersurface. It's only in a slice of coordinate space at a given time that the one object has multiple cross sections, manifesting as a pair of black holes to us, for now. None of the above is particularly an answer to the question of if there is compressed matter in an established black hole. In coordinate time, yes, it's very dense, but that's more like length contraction than pressure. None of the matter actually reaches the event horizon in coordinate time, and yes, in that state, it (the original collapsing star matter) is very much under compression. The singularity condition exists, but isn't described, precisely because the physics there is singular, sort of like asking what the perspective of a photon is like. Got a link? That sounds like pop nonsense. Is it peer reviewed? That makes more sense. Still, to be matter, it has to persist, no? Agree to all. There's also a naked singularity. You can for instance just keep dropping electrons into a black hole until the charge is more than the gravity and no more (isolated) electrons can be added by any means. Similar issues if the infalling matter adds too much angular momentum. A given mass can only have so much of that. These are examples of frame independent singularities not obscured by the coordinate singularity of the EH. Ditto with the LLM answers, which is just massaged google results. Anyway, thanks for the post. Good informative stuff in there.

Short term self-interest among plutocrats sounds like another way to say "capitalism." Or "late stage capitalism" anyway. I will try to answer your points better tomorrow.

Capitalism isn’t necessarily to blame, at least not as much as our failure to include negative externalities into the costs paid by producers and consumers of goods and services. Manufacturer doesn’t get fined for poisoning the water. Consumer doesn’t get taxed for continuing to buy goods from that manufacturer. The cycle of water poisoning persists while healthcare needs skyrocket and economic burdens get shifted (shafted?) to everyone downstream who weren’t ever even involved in the transaction. Carbon taxes were an attempt to address this and it want capitalism that made it fail. It was politics and short term self-interest among plutocrats.

so you googled a bunch of answers so tell me google what happened to the mass of the collapsing star then.... can you answer that or did it simply disappear. That is directed at google not you lol . Would you like to see equations that directly relate to the density term in regards to the collapsing star? https://arxiv.org/pdf/2310.17647 see section 4 If Victor Toth stated that then he only looked at the vacuum solutions of the interior and ignored the coordinate assigned for the singularity R=0. Not surprising though most articles tend to ignore that part as no one feels the singularity condition should exist. I have another related article that suggests that the BH may simply be a neutron star that has collapsed just beyond its EH but is still present. As mentioned no one knows beyond the EH. So its really anyone's game until we can find a means of indirect evidence to give us more clues. Gravity waves is a viable possibility others are mentioned here. The article that has some suggestive tests via the accretion disk is here https://arxiv.org/pdf/1104.5499 there is also a section covering Hawking radiation. However one will be quite surprised at all the processes matter undergoes in that accretion disk. I recall years ago I asked my instructor " How can you possibly have infinite density or near infinite density" his answer was that although fermions cannot share the same space with the same state that restriction does not apply to bosons. " you can in fact have extremely high density and still be a vacuum solution with incredibly high temperature and density. Vacuum describes a pressure term. Its not the energy density. You get the energy density by the equations of state for the particles contained within a region. Its one thing that often confuses ppl concerning vacuum. It can be positive or negative and can describe any range of energy density. If you think about that you might consider that a star is simply a condensed matter field it can be equally treated as a field. We know in cosmology we get a similar phenomena due to the BB and its mass density terms. I didnt have time to properly respond to the quoted section earlier as I was at work. Having time now I can provide a better response. just to add the singularity at r=0 is a true singularity it cannot be removed by a change in metric choice. The event horizon itself is often described as a singularity condition however that is a coordinate singularity and not a true singularity. https://en.wikipedia.org/wiki/Kerr_metric "Rotating black holes have surfaces where the metric seems to have apparent singularities; the size and shape of these surfaces depends on the black hole's mass and angular momentum. The outer surface encloses the ergosphere and has a shape similar to a flattened sphere. The inner surface marks the event horizon; objects passing into the interior of this horizon can never again communicate with the world outside that horizon. However, neither surface is a true singularity, since their apparent singularity can be eliminated in a different coordinate system. A similar situation obtains when considering the Schwarzschild metric which also appears to result in a singularity at 𝑟=𝑟s dividing the space above and below rs into two disconnected patches; using a different coordinate transformation one can then relate the extended external patch to the inner patch (see Schwarzschild metric § Singularities and black holes) – such a coordinate transformation eliminates the apparent singularity where the inner and outer surfaces meet. Objects between these two surfaces must co-rotate with the rotating black hole, as noted above; this feature can in principle be used to extract energy from a rotating black hole, up to its invariant mass energy, Mc2." I suspect this is what Victor Toth was referring to hope that helps Mathius Balu has an excellent coverage of this http://www.blau.itp.unibe.ch/newlecturesGR.pdf He will use the BH to help explain: "artifacts of coordinate choice" I would have to dig through it though to relocate the relevant section lol and just to add flames to the proverbial fire. A rotating BH has more than one event horizon..... google is useful but unless your aware of other factors getting good answers can often mislead down the wrong google pathway. For example simply googling BH singularity will more likely than not describe the coordinate singularities regarding the EH rather than the R=0 singularity condition. This wiki has the relevant detail regarding the Gravitational singularity as the link describes it The case r = 0 is different, however. If one asks that the solution be valid for all r one runs into a true physical singularity, or gravitational singularity, at the origin. To see that this is a true singularity one must look at quantities that are independent of the choice of coordinates. One such important quantity is the Kretschmann invariant, which is given by 𝑅𝛼𝛽𝛾𝛿𝑅𝛼𝛽𝛾𝛿=12𝑟s2𝑟6=48𝐺2𝑀2𝑐4𝑟6. At r = 0 the curvature becomes infinite, indicating the presence of a singularity. At this point the metric cannot be extended in a smooth manner (the Kretschmann invariant involves second derivatives of the metric), spacetime itself is then no longer well-defined. Furthermore, Sbierski[21] showed the metric cannot be extended even in a continuous manner. For a long time it was thought that such a solution was non-physical. However, a greater understanding of general relativity led to the realization that such singularities were a generic feature of the theory and not just an exotic special case https://en.wikipedia.org/wiki/Schwarzschild_metric#Singularities_and_black_holes

Technology basically facilitates tendencies and the issue is that especially younger folks are used to the instant gratification offered by things like technology (essentially everyone is carrying a dopamine machine with them at all times). I think we are a bit late in the game for that. The next generation of teachers are already not used to that anymore. In addition, the commodification of education and the increasing view of students as clients is starting to erode education in university as well. Educators in many systems across the world are struggling now to instill critical thinking skills and while it was already deteriorating over last decades, the COVID-19 pandemic has created a bit of a jump which makes things just way more visible otherwise. The reality is that we don't need an oppressive government or system to achieve those goals. That was very much a post WWII type of thinking. Now we have methods to do it voluntarily to ourselves, driven by capitalism, rather than political ideologies.

On any subject but UFOs I would agree with you. Let's do it!

But we’re talking about scientific analysis, which tries to remove such extraneous baggage from discussion (unless you are studying that particular phenomenon) Every time I have invited you to do a technical analysis of this you have declined. Which is unfortunate, because it would be interesting, but also means that this assertion is not based on actual science. Instead, it is (as some of my former students would say) a matter of pressing the “I believe” button. But one can’t pretend that this is science.