Bmpbmp1975

2 minutes ago, Ghideon said:

That is not how I interpret the article. It says the stars are missing from data that dates back to the 1950s.

https://ednews.net/en/news/sience/408284-researchers-have-identified-100-mysteriously-disappeared-stars-in-night-sky

 

I found the following passage interesting, it's from the abstract for the paper that the above article is based upon. The missing stars seems to have certain properties. I do not know what this implies (yet). 

Source https://iopscience.iop.org/article/10.3847/1538-3881/ab570f

 

I might get time to read the paper, think it's this one: https://arxiv.org/pdf/1911.05068.pdf

Not sure what that all means 

17 minutes ago, Mordred said:

It's random locations from what I could gather from the article. Keep in mind they are examining old images from the 50's. They do mention the possibility of scratches being one cause. Ie some of the supposed stars may not have existed. Ideally I hope they get other image samples from the same Era and run comparisons.

 

Thank you 

On 4/10/2020 at 9:00 PM, Bmpbmp1975 said:

Oh you don’t mean the void you mean where we are. Sorry misunderstood but there is no proof this ever happens and no reason to believe it could right?

Am I right

1 hour ago, Bmpbmp1975 said:

Thank you 

I was reading that part but does not clarify

4 minutes ago, Strange said:

It says "the naval catalogue spans around 50 years of sky surveys, capturing details of the entire sky." So I would assume that they are distributed throughout the sky. It would be remarkable if they had all been in the same location, so I imagine that would have been mentioned if that were the case.

Thank you 

Came across this interesting article about disappearing stars, there one minute gone the next. Curious to know is this in the same region of our galaxy or all over didn’t notice in the article that stated this?

https://m.ednews.net/en/news/sience/408284-researchers-have-identified-100-mysteriously-disappeared-stars-in-night-sky#.Xf35w8pHSXA.facebook
 

oh and happy Easter to all 

2 minutes ago, taeto said:

That is getting into what QuantumT is saying.  If we suppose that other universes keep bumping into our own universe, then it is practically impossible to tell when they might bump into one another at any particular location, such as ours. All that one can say then is that it will seem unlikely to happen.

Oh you don’t mean the void you mean where we are. Sorry misunderstood but there is no proof this ever happens and no reason to believe it could right?

2 minutes ago, taeto said:

I say "local timeframe", because what we can now see happening to them actually happened to them 3 billion years ago. The light did not arrive to us before now.

Whether it is the only one, that is an interesting question. There are other cool spots, but it seems there is only this particular very cold spot.

What we might worry about is that a different universe collides with our universe at or around the spot of our location, if this is what happens. But seeing that this possibility is very  hypothetical, I suggest that there is not real reason to worry.

No they were claiming that that is what caused it not that it’s going to happen there. Unless I missed something. And at the distance on 3 billion light years away even if it did we would not be affected in our lifetimes.  Am I correct 

5 minutes ago, taeto said:

The supervoid in itself is only hypothetical. But usually it refers to a unique very cold region determined by measuring the cosmic microwave background. It may be caused by not having a lot of galaxies present in a region of something like a diameter of 2 billion light years at a distance of about 3 billion light years from us, in our local time frame, and towards that particular direction. Or its detection can be caused by just local perturbance in the CMB itself called a cold spot. It seems not much to worry about. 

Why worry about it if it’s 3 billion light years away? Is there a reason to worry?

I was just asking if this is the only one. 
also not sure what you mean by our local timeframe

1 minute ago, pzkpfw said:

Ref: https://forum.cosmoquest.org/showthread.php?174262-Stephen-Hawking-last-work

 

Thanks o totally forgot about that

So 2 weeks before his death Hawking released a paper about the end of the universe. I believe it was called exit to eternal inflation. It states that one day I am not sure timeframe the universe will end because everything burns out.  I thought that that scenario already existed call Heat Death or something like that. So did he really predict this? 
 

or did I misunderstand his last paper?

Thank you 

but I thought that there was actually galaxies within the void. Also is this the only void

1 minute ago, taeto said:

I mean what happens with the research to figure out whether it is a supervoid, or just a normal cold region of the universe.

Now from my understanding there are many voids in the universe the supervoid is just bigger than the other. Am I correct?

also it is not growing in size?

and there are galaxies in the supervoid just not many and they are more spaced apart?

4 minutes ago, taeto said:

I think we simply have to wait and see what happens. We can of course be sure that it will not hit us during our lifetime.

See what happens with what?

also I was under the impression that the supervoid is not growing. Or am I wrong

concodering the supervoid is 3 billion light years away I hope not in our lifetimes 

Just now, taeto said:

Well, if there is indeed an observed cold spot originating from a collision with a different universe, then it stands to reason that there quite many such collisions that occur, possibly even infinitely many of them. But as you say yourself, the idea is far fetched.

That’s what the article states. I think theta de talking about the supervoid though 

I found this article kind of cool it talks about how the cold spot can actually be made from a dent with another universe. They do think the idea is far fetched though.

https://www.scientificamerican.com/article/could-cold-spot-in-the-sky-be-a-bruise-from-a-collision-with-a-parallel-universe/
 

anyone have thoughts on this, also I always thought they there were more than 1 cold spot in our observable universe would that mean multiple collisions?

8 minutes ago, zapatos said:

I suspect the answer to your question is "no". I'm afraid it may be time for you to recognize that the conversations on this site are simply above your comprehension level.

You don’t have to if you don’t want to but a few people have been helping me learn already on this post 

1 hour ago, MigL said:

But there is a small possibility that this apparent anisotropy is due to other reasons ( Cosmological Constant, or Dark Energy anisotropy ? ).
Since we are not sure, it is called 'dark' flow, or motion.

Can someone explain this better to me

does this tie in what mordrez explained to me or is it different 

5 minutes ago, Mordred said:

The paper isn't a wide range of area study. It has only examined the nearby 313 galaxy clusters out of billions of galaxies.

 It cannot state anything beyond its examination range which I have given.

It also explains dipole anistropy in its opening paragraphs.

 

 

So as I stated nothing to fear in our lifetimes?

5 minutes ago, pzkpfw said:

  

 

 

Even if it were expanding 30% quicker in some areas, why would that be a concern in our lifetimes?

Why is that always a conclusion you jump to?

if it expands quicker it ends quicker 

Just trying to understand since this is local galaxy cluster 

3 minutes ago, Mordred said:

Correct the range in this paper is 3.026 Gly or if you prefer 926 Mpc. Assuming my calculations is correct. This gives a range to z=0.3 in cosmological redshift value.

 The universe has a radius of roughly 46.5 Billion light years. 46.5 Gly. Z= 1096 roughly

We are examining only a miniscule portion of the observable universe.

3.026 Gly out of 46.5 Gly.

Local group only... And only a small sample of the observable universe.

 

So the universe is not expanding 30% quicker in certain areas, and this is not something for us to worry about in our lifetimes then

16 minutes ago, Mordred said:

Let's simplify then start with the detail telescopes no matter how advanced can only detect and measure out to a certain range.

 With advanced telescopes that range depends on what frequencies of light they are sensitive enough to receive.

"Chandra is sensitive to X-ray sources 100 times fainter than any previous X-ray telescope, enabled by the high angular resolution of its mirrors. Since the Earth's atmosphere absorbs the vast majority of X-rays, they are not detectable from Earth-based telescopes; "

The Chandra telescope is designed to detect wavelengths between 0.12 and 12 nm. As per the link

https://en.m.wikipedia.org/wiki/Chandra_X-ray_Observatory

this limits its range of detectability.

Do you understand this thus far ?

the next step is to look specifically at the range of examination in the paper itself...

Yes I do it’s range of detection is limited 

1 hour ago, Mordred said:

To understand the term brightness one has to start with the mass to luminosity ratio.

https://en.m.wikipedia.org/wiki/Mass–luminosity_relation

This is a particular topic that is extremely difficult to present. However in essence it means that the matter ratio from one hemisphere locally appear different from another local hemisphere 

(I stress local region as this is where the difference is examined) it does not apply to far field measurements as Chandra does not have that capability.

So the 30% has nothing to do with the speed of expansion compared to another area then.

and I am still trying to understand what you mean about local regions and how this has to do with the paper 

you keep bringing up short distance of Chandra so if this is closer is this a concern

modred yesterday understood everything you thought me, today not so much lol

7 minutes ago, Mordred said:

The problem with your understanding is paying too much attention to pop media coverage or the verbal word aspects in descriptives.

Let's take universe age for example I showed an inverse relationship between Hubble constant to age of universe.

t=1H now let's assume a start point of H=73/km/sec/Mpc. 

 Then let's assume an extreme (believe me this is an extreme easily discovered and highly unlikely) of 10 percent from one hemisphere to the other. 

Using the above formula the difference is roughly less than 30 million years. The different datasets such as HOLIVOW etc already noted a margin error of 6 Mpc/sec/Mpc between local group and far range measurements. Yet these all equate to fine tuning.

None of this is as profound as media tries to make them. 

Particularly since the Chandra telescope can only examine a limited range of frequencies that correspond to our local region.

It can never get the full picture.

Thank you now what does the 30% difference of brightness mean does that mean the rate is 30% faster 

"Together with colleagues from the University of Bonn and Harvard University, we looked at the behaviour of over 800 galaxy clusters in the present Universe," says Konstantinos. "If the isotropy hypothesis was correct, the properties of the clusters would be uniform across the sky. But we actually saw significant differences."

properties, with similar temperatures, appeared to be less bright than what we would expect in one direction of the sky, and brighter than expected in another direction," says Thomas. "The difference was quite significant, around 30 percent. These differences are not random but have a clear pattern depending on the direction in which we observed in the sky

https://www.google.ca/amp/s/phys.org/news/2020-04-basic-assumption-universe.amp

3 minutes ago, Strange said:

This can be important, exciting, revolutionary, dramatic, etc without being anything to worry about.

Of course it would be a big deal if we discover something new about the universe. That is what scientists (and people who are interested in science) hope for. 

Why do you think that learning new stuff is a worry or a bad outcome? Just stop posting that sort of stupid comment.

I got the 10% from the estimate you gave before I am sorry. I think they said the earliest the universe can end is 2.8 billion years. Looking at 10% less I am sure I won’t be alive by then

thanks for your help