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Everything posted by Strange
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The beginning and end of the universe?
Strange replied to SimonFunnell's topic in Astronomy and Cosmology
You are mixing up a couple of things here, with both the big bang model and the theory of evolution. In both cases, we don't know how things started. We don't know how or if the universe was created (I am sceptical about claims that the universe was created in the big bang, but there is no evidence one way or the other currently). We also don't know how life came about - although science has moved on a long way from "primordial soup" and there some very interesting hypotheses around. One the other hand, we have a huge amount of evidence about how the universe evolved from an earlier, hotter, denser state. Similarly, we have a huge amount of evidence for the way species have evolved over time. In both cases, we have good scientific theories describing evolution: the big bang model of the universe and natural selection for biological evolution. In both cases, as well, the initial simple model has had to be modified as we learn more. So, very recently, we have had to extend the big bang model to include accelerating expansion ("dark energy") and biological evolution has had to be extended to include horizontal gene transfer (Darwin and Wallace didn't even know genes existed) epigentics, and many other things. I agree. Firstly, as I say, there is no evidence for "creation" of the universe (like abiogenesis, there are many hypotheses for what might have happened at the earliest times). Secondly, journalists and popular science writers (including scientists) rarely add the caveats such as "according to current evidence ... our best theories ...". They use words like "prove" and "know", whereas science is normally expressed in much more cautious terms such as the evidence "supports" or "is consistent with" a hypothesis. They also never say that what they are saying is based on images and analogies, which are only an approximation to the science (and, in some case, are just not true). But I don't think you should be too quick to discard carefully developed and well-tested theories just because they are overhyped and simplified in the popular press. One of the values of science forums is (I hope) that you can get an insight into the deeper science behind the pop-sci articles and videos. This approach, of giving simplified versions, is common in education. If you go to university, you soon realise that the "facts" you learned at school are not really true, and the real scientific "facts" are more complex. And then, as you study more you realise that those are not facts, they are just good models, and some models are better than others. This approach to education is sometimes known as "lying to children". Some people get very upset when they find out they have been "deceived" in this way. But I'm not sure there is an alternative. You can't teach the complexities of general relativity to schoolkids so you teach them Newton's law of gravity and you give them some simplified stories about "rubber sheets" to introduce some of the concepts from GR. Anyway, stick around. Ask questions. Hopefully, you will be able to fill some of the gaps and see that the science does (usually) have a pretty sound basis. Even though we don't know anything for sure and nothing is every proved. -
Why do geodesics of space-time cause elliptical orbits in our dimension?
Strange replied to bluescience's topic in Relativity
Because the orbiting object started with some motion (which was not perfectly directed towards the centre of the thing it is orbiting). Those objects which didn't have enough speed will fall out of orbit. Those that had too much speed for a stable orbit will leave the system. The rest will find a stable orbit. -
The beginning and end of the universe?
Strange replied to SimonFunnell's topic in Astronomy and Cosmology
Annoyingly, you don't pose questions. You make assertions based on your lack of knowledge. -
What difference does it make if the Schwarzschild radii touch?
Strange replied to Robittybob1's topic in Relativity
No difference at all. How could it. -
The beginning and end of the universe?
Strange replied to SimonFunnell's topic in Astronomy and Cosmology
Not true. (Like pretty much all of your claims about existing science.) -
Larry Wall (inventor of Perl) wrote that the three virtues of a programmer were laziness, hubris and impatience.
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SCIENCE - What actually is Science ?
Strange replied to Mike Smith Cosmos's topic in General Philosophy
The transistor was designed using the mathematics of quantum theory. -
What difference does it make if the Schwarzschild radii touch?
Strange replied to Robittybob1's topic in Relativity
(To answer your question from the other thread: http://www.scienceforums.net/topic/94060-what-is-the-best-3d-description-of-gravitational-waves/?p=913986) But don't discuss that further here! -
What is the best 3D description of Gravitational waves?
Strange replied to Robittybob1's topic in Speculations
And the paper I linked to earlier shows some more accurate approximations for what happens with two black holes getting quite close and also notes that, even before they merge, you need to simulate the full equations of GR. That is the only way you are going to understand the source completely. -
What is the best 3D description of Gravitational waves?
Strange replied to Robittybob1's topic in Speculations
Citation needed. That does not seem to be what your equations say. That equation only tells you orbital frequency. It says nothing about gravitational waves. The equations you are using are approximations based on a point source. It assumes that the gravitational waves come from that point source but says nothing about how they arise (because at the distance these equations are valid, the nature of the source doesn't matter too much). -
The beginning and end of the universe?
Strange replied to SimonFunnell's topic in Astronomy and Cosmology
This sounds like some of the multiverse and eternal inflation ideas. Various claims have been made for patterns detected in the CMB that these are evidence for various such theories. For example: http://www.dailygalaxy.com/my_weblog/2009/12/is-the-massive-cold-spot-a-sign.html https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology#Empirical_tests -
What is the best 3D description of Gravitational waves?
Strange replied to Robittybob1's topic in Speculations
The height of the wave depends on distance, time and the angle of the observer: I don't know what you mean. It IS a pulsing signal. A sine wave. At any position in space, you will see a sine wave. The intensity depends on your distance and the angle. A better analogy might be a (food) mixer with two paddles rotating around a common centre - and also each rotating. This would produce all sorts of complex motion in the water nearby but a few metres away, you would just see ripples spreading out in a circle. I'm not sure what you are failing to see here. You mentioned a spiral. These equations do not describe a spiral. If that were the case then the [latex]\theta[/latex] term would have to appear in the final part of the equation in order to describe a change of phase as you change your angle wrt the source. -
What difference does it make if the Schwarzschild radii touch?
Strange replied to Robittybob1's topic in Relativity
It doesn't say anything about "inside" or "singularity". It seems to me to be just testing whether the (merged) black hole behaves as predicted by GR. If it doesn't, that will be pretty exciting because that may provide the information needed to work out how GR needs to be modified. It is possible that a version of GR that includes quantum effects might mean that event horizons are not as impenetrable as we currently think. But that is all unknown at the moment. We can only work with the theory we have. Forget about particles. We are dealing with black holes that have mass but no structure (in current theory). -
SCIENCE - What actually is Science ?
Strange replied to Mike Smith Cosmos's topic in General Philosophy
Remember the step before Maxwell: Faraday. A meticulous and brilliant experimenter. It was largely (only?) because of his work that Maxwell was able to develop his mathematical description. (Which Faraday always rather resented; you and he may have got along rather well!) -
What is the best 3D description of Gravitational waves?
Strange replied to Robittybob1's topic in Speculations
See imatfaal's excellent breakdown in post #110 (http://www.scienceforums.net/topic/94060-what-is-the-best-3d-description-of-gravitational-waves/?p=913689) That describes each "pulse" (sine wave). -
What difference does it make if the Schwarzschild radii touch?
Strange replied to Robittybob1's topic in Relativity
All you know about the mass is that the black hole has that mass. The event horizon is not a "thing". It is a location. WE DON"T KNOW WHAT HAPPENS TO THE MASS. I skimmed that (most of it is way over my head) and didn't immediately see anything related to that. Can you point out where it says that? -
What difference does it make if the Schwarzschild radii touch?
Strange replied to Robittybob1's topic in Relativity
They don't instantly combine. They merge (pretty quickly). The fastest the event horizon can grow is c. -
What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
Why do you refuse to give straight answers to questions? Are you trolling? What subjective conclusion? What logic is defied? What about the evidence is "elusive"? You keep making these vague claims but you provide nothing to back them up. Perspective. I assume you mean Trump/ Of course you don't. There is no proof in science. But you don't even have evidence. -
What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
What subjective conclusion? What logic is defied? What about the evidence is "elusive"? You keep making these vague claims but you provide nothing to back them up. -
Nice analogy. And the reason the electron doesn't reach the nucleus is because there are no more steps: the ground floor is at a non-zero energy level.
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What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
The reason it is not accepted (even though your concept is well understood) is because you have no data to support it. Exactly. Stop doing that. You are emotionally tied to your idea (even though there is no evidence for it) and you are emotionally opposed to the current model (even though it is entirely based on evidence). Your emotional bias cause you to make dishonest statements and make you unwilling to learn. -
What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
So give up on your beliefs and follow the logic of science instead. Don't assume science is wrong just because you don't like its answers. -
What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
It has nothing to do with trust. It is the complete absence of any evidence or quantitative data supporting your idea that is the problem. -
What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
I would start a new thread if you have questions about black holes. -
What is all the evidence for an Expanding Universe
Strange replied to shmengie's topic in Speculations
I assume by precept you mean premise? Logic is impossible without premises, that is what the logical argument builds on. This is how science develops models that are based on evidence (not kicking out some of the evidence because you don't like the results - that would be dishonest). It is not that generic. In fact it is a specific form of the big bang model that includes the amount of dark energy (Λ) and dark matter (CDM) that we observe in the universe. What does that have to do with "logic"? Surely, it is logical to modify the model to fit what is observed? What is not logical is claiming that you have a magic answer when you have no model and no data.