Ask Me Anything AMA with Dr. Joe Pesce

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I am an economist but my hobby is cosmology, thus my trial to comprehend and understand the functioning of the universe is way different than presented in academic textbooks. I realize that Astronomy is not the same thing as Cosmology but they have common anchor points.
My questions won't be complicated and just two.

1st question:
What do you think about ether? Is it present in the Universe or not?
My opinion is that the ether exists and below is the link to my article justifying my point of view:

2nd question:
In my article titled
http://www.eioba.com/a/4f0v/gravity-how-to-understand-it
I proposed to distinguish the poles (N and S) in the nucleus of the universe and to denote its equatorial zone (first). Well, the N and S poles would be in opposite places of Great Voids. On the other hand, the equatorial zone, would be where Filament Galaxies occur. I just don't know if my suggestion coincides with the actual distribution of the above-mentioned voids and galaxies. Kindly confirm or deny my assumptions.

Kind regards
 
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DrJoePesce

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The work of Halton Arp (Harvard, Caltech) and Tom Van Flandern (Yale, Chief of the Celestial Mechanics Branch of the Nautical Almanac Office), and many others suggests that the "big bang" model of cosmology has major (often fatal) flaws. For example, see Van Flandern's list of the Top 30 Problems with the Big Bang (https://www.spaceandmotion.com/cosmology/top-30-problems-big-bang-theory.htm)

As you correctly pointed out in an earlier post, the hallmark of a useful scientific model is its ability to predict future observations. A model that misses badly in its predictions, or is so laden with adjustable parameters that it cannot be falsified, is an unscientific model.

Given this fundamental tenet of the scientific method, why is it that so many cosmologists retain undying faith in the "big bang" model? By any objective account, its record of prediction is very poor.

Surely, you will disagree with this assessment, but I think the record is clear. The BB needs multiple adjustable parameters to survive. Interested readers can reference the source I cited above for more information.

My question to you, Dr. Pesce, is a simple one: Is the "big bang" model falsifiable?

I have started forum threads before asking precisely this question and, despite dozens of responses, I have never heard a BB proponent give a straight answer on this question. I think this says a lot about the model. If no one can think of an observation that would invalidate the BB, isn't that a problem? I say it is. A gigantic one.

In response to my question, I hear people defend the model by saying, "well, the BB is not perfect, but there's no good alternative." I disagree. As TVF points out in the link above, static universe models fare well against the BB, without the requirement for inventions like dark matter. However, the point I will always make in response is that no one should accept a shoddy, non-predictive model simply because he can't come up with a better one. Shoddy is shoddy. A true scientist will be comfortable with no answer rather than the *wrong* answer.

So again I ask: what observation could cosmologists possibly make that would falsify the BB?
Thanks for the question Robotron. Cosmology is not my area of expertise, so rather than discussing details of different models, let’s look at this at a somewhat higher level. First of all, the big bang model of today is not the big bang model of the 1940s, so we need to distinguish this (and, formally, we shouldn’t call it the big bang model, but that’s ok as long as we understand that current views have changed). This gets to a major point of science: We never have a full, complete, understanding of anything, so our models and explanations are always going to change, be falsified and abandoned, or just tweaked. Questioning how models explain nature is another major aspect of science.

It’s not necessarily true that a model that misses in predictions is “bad” – it might be, but it could also reflect on our understanding (so the ability to ask the right questions), our technology (not good enough to see in the details we need), etc. I have many examples over my career when my explanation of an observation was completely wrong when we made another observation with a better instrument. Astronomy/cosmology is still in discovery space.

The big bang model is absolutely predictive: it makes many predictions (an important one being the Cosmic Microwave Background Radiation). And it’s falsifiable. Again, we just haven’t be able to falsify it – either because it is correct or because of the issues mentioned above. Just because we can’t think of predictions that would falsify a model doesn’t say anything about the quality of model.

And, again, tweaking a model doesn’t make it bad; that’s science. Now, if a model has to be tweaked so much, or there are a huge number of assumptions, compared to another, competing, model, then Occam’s razor should be applied. All models have pros and cons, the one with the fewer negatives and assumptions is the one we adopt as a working model moving forward (but of course it doesn’t mean it is correct, ultimately).

Scientists don’t like being wrong (we are human, afterall!), but are generally open to being wrong. And this is another hallmark of science. Questioning models/hypotheses/theories is what it’s all about – and that’s all good.
 
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DrJoePesce

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Dr Joe
  1. Is the dark matter that slows spiral galaxies from collapsing the same as is found at accretion disc scales?
  2. What evidence is there for dark matter in AGN and if it is same as in 1. above, does it slow down accretion discs matter from collapsing into black holes.
  3. How does dark matter manifest alongside CMB and its inhomogenieties?
  4. Dark energy and dark matter- they have interaction or any other relationship?
  5. Are there alternate phenomena we know that are equivalent of dark energy, such as loss of matter in blackholes, rate of conversion of matter into energy, etc?
Dr Ravi Sharma - hello!

Dark matter seems to be distributed like matter (or vice versa). I think dark matter is keeping spiral galaxies from flying apart, not collapsing. While there is almost certainly dark matter in an accretion disk, I don’t think it is having any effect on the disk’s overall behavior and properties.

As for the CMB: it’s “clumpiness” is a fossil of the variations that probably led to matter accumulation – so matter and dark matter are affected (probably similarly) by this. Otherwise, I don’t think there is any other connection between CMB and dark matter. I think the CMB photons can reflect off of some dark matter candidates, but I don’t think that has been observed.

There shouldn’t be any special connection between dark energy and dark matter either. Dark energy seems to be causing the expansion rate of the universe to increase, and so dark matter is experiencing that expansion just like ordinary matter.

We are still trying to understand dark energy and what it is, so stay tuned. Matter isn’t lost in black holes – that mass remains. What IS lost is information.
 
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DrJoePesce

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Hi Dr. Joe !
Here is a fun question related to Star Trek.
If Warp 1 is the speed of light, and Warp 9.9 is roughly 2000 times that, would not the Enterprises" 5 year mission equate to lifetimes depending on where the Enterprise happened to travel to ?
In such a scenario, would the Enterprise often meet with its more advanced progeny on its way back to Earth? As Mr.Scott asks in the rebooted Star Trek movie...."you're from the future? Are there still sandwiches?"
Fun question indeed!

Well, sadly, Star Trek is science fiction. So, what I can say is if we could travel at the speed of light, there would be time-dilation effects. I don’t know what sort of effects there would be with faster-than-light travel, since that appears not to be possible. Since Star Trekian propulsion is science fiction, I guess we can imply that the warp drive affects space-time in a way that eliminates time-dilation issues.
 
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DrJoePesce

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So I have two batch of questions. The first ones are scientific and the 2nd batch of questions is more personal.

What do you think is outside our universe? What is our space expanding to?
How do black holes gain more mass because at a certain point in the gravity well even light stops?
What kind of an attitude would you take if you knew there was extraterrestrial species? Should we let them be or get to them? Would the risk be reasonable?
How can we trust reality? Even though we have the scientific method, some things probably can change.
How do you feel about the rate of scientific development? Could things be going too fast, say. We really don't understand what we have found and we put things to use too quickly?
Is climate change a immediate threat to us?
Should science and religion support each other or be their separate entities?
Is it okay to mix and match old and new ideas together to make something new?
Isn't existing in space (like how we already are) really dangerous? Like there's asteroids, massive black holes, space dust, solar rays...
Could we some day inhabit/ terraform other planets?
Would a dyson sphere be a good idea or even like really big solar panels closer to a star with some protection and some way of transforming down to a surface?
What do you think is the most optimal way to settle on a planet time/resource wise?
How many people would you need to run a new place like that and keep propagating?

Is it just chance that we are here or was it set to be by a fate of a sort or more like a deterministic approach A leads to B and so fourth since the beginning of the universe? We just happen to be in a Goldilocks zone?

What is your favorite Star Trek? Have you seen them all? I am currently watching the series Discovery after seeing the others.
What music do you like?
How did you get where you are now? Are you happy to be doing what you're doing? Has your family played part in it?
Why do you do what you do?
With that, have you had hard obstacles or personal loss. How have you got through that, how have you had kept a hope up in hard moments be it related to anything?
Do you have a favorite dish or something you eat a lot?
Do you exercise?
Do you have any hobbies besides the area of your expertise?
Have you read any good physics/astronomy books, what are they?
What about classical literature, e.g "The Greats"`?
How do you manage to work for long if you have to? What helps to keep you up?
*Oh also. What do you think about science youtube channels? Veritasium, Vsauce x, numberphile, etc etc?

Thank you for your time Joe. And all of you. Stay safe.
Thanks Terracraft for so many questions, let me try to answer a couple here:

- There's essentially no limit to growth of a black hole. As mass is added, the mass of the black hole increases. Remember, we can't get rid of mass - it can only accumulate or be converted in to energy.

- mix and matching of old and new ideas is great and happens all the time. Most of what is new has been built on the old. That doesn't mean that new ideas can't be completely separated from the past, but it's rare and unusual! (For example, Newton's explanation of gravity is old, but Einstein didn't eliminate it, just built on it.)

- space is really dangerous! As you point out - chunks of rock and metal flying around, stars exploding, cosmic rays, energic electromagnetid radiation (x-rays, gamma-rays)....

- Favorite Star Trek: Series = The Original Series. Episode = really difficult to choose, but maybe Amok Time....
 
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DrJoePesce

Verified Expert
Mar 31, 2020
88
229
410
I am an economist but my hobby is cosmology, thus my trial to comprehend and understand the functioning of the universe is way different than presented in academic textbooks. I realize that Astronomy is not the same thing as Cosmology but they have common anchor points.
My questions won't be complicated and just two.

1st question:
What do you think about ether? Is it present in the Universe or not?
My opinion is that the ether exists and below is the link to my article justifying my point of view:

2nd question:
In my article titled
http://www.eioba.com/a/4f0v/gravity-how-to-understand-it
I proposed to distinguish the poles (N and S) in the nucleus of the universe and to denote its equatorial zone (first). Well, the N and S poles would be in opposite places of Great Voids. On the other hand, the equatorial zone, would be where Filament Galaxies occur. I just don't know if my suggestion coincides with the actual distribution of the above-mentioned voids and galaxies. Kindly confirm or deny my assumptions.

Kind regards
Imposing a coordinate system on the universe is practically what you are suggesting. We have such an Earth-centric coordinate system already. And we use a collection of quasars to tell us with great accuracy our (Earth's) position in the universe. So this is useful for astronomcal observations and other Earth and solar system activities. Other than that, such a system really would have limited utility since there is no "preferred" location in the universe.
 
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DrJoePesce

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Mar 31, 2020
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Dr Ravi Sharma - hello!

Dark matter seems to be distributed like matter (or vice versa). I think dark matter is keeping spiral galaxies from flying apart, not collapsing. While there is almost certainly dark matter in an accretion disk, I don’t think it is having any effect on the disk’s overall behavior and properties.

As for the CMB: it’s “clumpiness” is a fossil of the variations that probably led to matter accumulation – so matter and dark matter are affected (probably similarly) by this. Otherwise, I don’t think there is any other connection between CMB and dark matter. I think the CMB photons can reflect off of some dark matter candidates, but I don’t think that has been observed.

There shouldn’t be any special connection between dark energy and dark matter either. Dark energy seems to be causing the expansion rate of the universe to increase, and so dark matter is experiencing that expansion just like ordinary matter.

We are still trying to understand dark energy and what it is, so stay tuned. Matter isn’t lost in black holes – that mass remains. What IS lost is information.
By the way, I forgot to add that dark matter is found wherever we look for it. So AGN, being galaxies, certainly have dark matter (more than the visible matter), and cluster of galaxies in which most galaxies are found have lots of dark matter too.
 
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DrJoePesce

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Mar 31, 2020
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Hello All - our week together is rapidly coming to a close. I had a blast! And your questions were fantastic!

Keep up the interest and keep looking up!

I hope to be with you all again some time.
 
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