Ask Ethan: Could ‘Cosmic Redshift’ Be Caused By Galactic Motion, Rather Than Expanding Space? (link)
A reader asks,When we observe a distant galaxy, the light coming from the galaxy is redshifted either due to expansion of space or actually the galaxy is moving away from us. How do we differentiate between the cosmological redshift and Doppler redshift? I have searched the internet for answers but could not get any reasonable answer.Understandable that he couldn't find a reasonable answer. How do I find out how much redshift is attributable to normal cosmic motion, and how much to expansion of the universe, which is still motion, but also isn't? It's not exactly a reasonable premise.
As it turns out, there are actually a total of four possible explanations for the redshift-distance relation we observe. They are as follows:Notice how effortlessly he sets up a Sherlock's Folly? Provide four possible theories, and eliminate three with evidence. Thus, the remaining one must be the truth! This argument assumes (1) that there really are only four possible theories, and (2) that all presumptions are correct. In this case, to assume that there really is a redshift-distance relation. What if there isn't? A lot of complexity has to be added if it's true. For instance, quasars - which are highly red-shifted - are forced to be "extremely luminous" objects only in distant space that only existed in the early universe, and thus none are observed in our nearby space. Some quasars are so impossibly bright that scientists have to invent additional explanations. Quasars are said to be directional, thus only the quasars that happen to be oriented towards Earth are observable. Also, the brightest quasars were determined to be gravitationally lensed, increasing apparent luminosity by an order of magnitude. On top of all that, of course, is the cosmic inflation theory, with all it's requisite suspension of doubt.
- The light from these distant galaxies getting “tired” and losing energy as they travel through space.
- Galaxies evolved from an initial explosion, which pushes some galaxies farther away from us by the present.
- The galaxies move rapidly, where the faster-moving, higher-redshift galaxies wind up farther away over time.
- Or the fabric of space itself expanding.
A simpler explanation is that quasars are not vastly distant objects, thus not impossibly luminous, and we currently don't know why they are so red-shifted. This hypothesis is not considered by modern astronomers. Redshift theory is assumed to be true. Thus, all theories it depends on - such as accretion disks that account for "extreme" and "hyper-luminous" emissions of x-rays and gamma rays - and all resulting theories - such as cosmological expansion - must also be true.
If we lived in a Universe where the distant galaxies were so redshifted because they were moving away from us so quickly, we’d never infer that an object was more than 13.8 billion light-years away, since the Universe is only 13.8 billion years old (since the Big Bang). But we routinely find galaxies that are 20 or even 30 billion light-years distant, with the most distant light of all, from the Cosmic Microwave Background, coming to us from 46 billion light-years away.Contemplate how nuts that sounds. The redshift theory contradicts Big Bang theory. The resolution is a yet another bizarre theory, this one of unexplained cosmic inflation caused by "dark energy." It's not quite clear to me why physicists wouldn't just assume that the speed of light has slowed down, which would have the same effect without the needed magical dark energy. I suppose it's because the speed of light is believed to be a fundamental constant, and the community utterly fails to challenge its own belief systems.
It’s important to consider all the possibilities that are out there, as we must ensure that we’re not fooling ourselves by drawing the type of conclusion we want to draw. Instead, we have to devise observational tests that can discern between alternative explanations for a phenomenon. In the case of the redshift of distant galaxies, all the alternative explanations have fallen away. The expanding Universe, however unintuitive it may be, is the only one that fits the full suite of data.Please take a moment to appreciate the utter hypocrisy of this paragraph. The modern scientists are very, very good at pretending that they apply logical and scientific rigor, and very bad at actually doing so. They absolutely do not "consider all the possibilities that are out there." They certainly won't consider the possibility that the redshift-distance relation is faulty.
5 Killer Events From Space That Could Wipe Out Human Life On Earth (link)
Ethan lists 5 cosmic events that could devastate Earth.
- Comet/asteroid strike
- Gamma-ray burst. Certainly possible, but the diagram shows gamma ray bursts as caused by colliding neutron stars, which is fantasy.
- Random encounter. Effectively the same as #1.
- A supernova.
- Our own sun, which will consume the Earth in 2 billion years. The sun-eats-earth prediction is based on a theoretical model for star lifecycles, of which there isn't really any evidence, and I don't believe to be true. Of much more concern should be a catastrophic CME event, which would be similar to an EMP nuke attack on the US, which would fry our electrical grid. The DoD has estimated that such as an event would kill half of Americans within a year, and as many as 90% overall.
This Is What’s Special About A Full Supermoon Occurring On The Equinox This Year (link)
Ethan provides some interesting facts about the supermoon coming up on March 20th... on March 26th. I guess he was off by about a week on that one.
What Was It Like When Oxygen Appeared And Almost Murdered All Life On Earth? (link)
An interesting piece on the great oxygenation event which caused a catastrophic extinction event on Earth and an extreme glacial period. Keeps allusions to current-day CO2 emissions, which are having a "massive impact on Earth's climate", to a minimum.
No, Quantum Tunneling Didn’t Break The Speed Of Light; Nothing Does (link)
A lengthy article refuting recent science reporting which claimed that quantum tunneling breaks the speed of light. He ends with this sentence.
But going faster than light? That’s still restricted to the realm of science fiction alone.As if he shies away from science fiction.
One Of These Four Missions Will Be Selected As NASA’s Next Flagship For Astrophysics (link)
There is always a concern that the big-budget missions will be dedicated towards some nonsense science - for instance, LISA, a proposed gravitational-wave detecting satellite. The four missions Ethan covers are all dedicated to general astronomy, and thus valid scientific ventures.
Ask Ethan: Why Haven’t We Found Gravitational Waves In Our Own Galaxy? (link)
The question asks,
Why are all the known gravitational wave sources (coalescing binaries) in the distant universe? Why none has been detected in our neighborhood? […] My guess (which is most probably wrong) is that the detectors need to be precisely aligned for any detection. Hence all the detection until now are serendipitous.He responds,
If we come forward to the present day, we’ve actually detected a large number of mergers: 11 separate ones thus far. [...] If we look at the distances to these objects, though, we find something that might trouble us a little bit. Even though our gravitational wave detectors are more sensitive to objects the closer they are to us, the majority of objects we’ve found are many hundreds of millions or even billions of light-years away.He gives two explanations for why we haven't seen any sourced from within our own galaxy, or anywhere near, for that matter.
But again, we have not observed them in our ground-based gravitational wave detectors. And there’s a simple, straightforward reason for that: our detectors are in the wrong frequency range!And
It’s true: during the time that LIGO and Virgo have been operating, we haven’t seen any mergers of black holes or neutron stars in our own galaxy. This is no surprise; the results from our gravitational wave observations have taught us that there are somewhere around 800,000 merging black hole binaries throughout the Universe in any year. But there are two trillion galaxies in the Universe, meaning that we need to observe millions of galaxies in order to just get one event!It's not clear to me how they've inferred, from several observations over several years, that 800,000 black hole mergers occur in a year, but we'll assume it follows logically from their premises. There is a sound argument to make that, if we can detect events out to billions of light years, and only 11 have been seen, then the odds of any being nearby are faint indeed. However, there is another possible explanation, which Ethan would likely not consider. As described in More Tax Dollars for Gravitational Sinkhole, the gravitational detection process consists of looking at a very noisy signal, removing the noise somehow, and then seeing if what's left matches a hypothetical signature from a catalogue of over twenty thousand possible scenarios. That is our major complaint with the ground-breaking results. It seems that, whatever is detected, they'd eventually find something that looks like one of the signatures.
What they've found so far have been weak signals buried in the noise, so they're thought to come from great distances away. A nearby event would create signal many orders of magnitude stronger, which would clearly jump out from the noise. There would be no need for clever - and questionable - noise-canceling techniques. So here's the rub: if they're really just picking up false positives from the noise, they will never see a powerful, nearby signal. The detected gravitational waves are weak and "distant" because they would have to be if gravitational waves don't really exist.
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