Between 100 days and 3 years we will record what will be the single largest energy release we have ever recorded.
To give an idea of our records so far: our detection of black hole mergers around the 100-150 solar masses scale are just behind a couple gamma ray bursts as the single largest energy release ever.
How big are the black hole mergers around 150 solar masses and the two largest gamma ray bursts?
The energy release converted the mass of between 1-6 solar masses into energy.
With black hole mergers this energy release/conversion is in the form of gravitational waves that we then detect!
So imagine the sun, times 6, every atom, converted into that energy. That’s what we have already recorded.
This predicted one is not even in the same ballpark. Those 1-6 sun matter into energy conversions are ants compared to what’s coming.
These supermassive black holes are thousands to tens of thousands of times the mass of our sun. (Not sure if the ones in this paper are in the billion solar masses class. Yes they do exist)
This event will convert the mass of perhaps a hundred or a thousand suns worth of matter into energy in an instant. (Not sure if the paper gives any accurate predictions I’m lazy!)
>"With black hole mergers this energy release/conversion is in the form of gravitational waves that we then detect!"
FWIW, these gravitational waves are too low in frequency for LIGO to catch. The paper says it would be within detection range of LISA (the ESA's space-based laser interferometer), but unfortunately they haven't launched that yet.
However, there's a related effect that could be measurable some 5-10 years afterwards:
>"They should, however, leave an imprint on spacetime itself, a sort of relaxation of distance and time dubbed gravitational wave memory, which could be detected over many years by monitoring the metronomic pulses of spinning stellar remnants known as pulsars. “It’s a very tricky signal to measure,” Ransom says, “but that would be definitive, a total smoking gun” of merging supermassive black holes."
Pulsar-based galaxy-wide gravitational wave observing is one of the most intriguing (while being conceptually simple and understandable) concepts I've come across.
I wonder if this predicted supermassive black hole merger is rare for us - once in a lifetime, or we find out after LISA is operational that they happened frequently.
Am I right in thinking that the search area something like LISA and LIGO "see" is essentially the entire observable universe?
Could we could catch a merger from the first billion or so years of the universe?
I found out about this channel a couple of days ago, and since then, I have watched a large chunk of the content. Rather than looking for something to kill time with on the boobtube, I've killed some time with this channel.
The chirp doesn't go to infinite frequency. The last rotation of the two black holes happens in some finite time, a time scale that gets longer the larger the black holes are.
If I read this correctly, the black hole binary is about 40 million solar masses and could be five times that. Our own black hole at Sgr A* is only a tenth of that.
This has to be a really rare occurrence. Hopefully, it won’t be behind the sun when it coalesces, though that won’t hide the gravitational effects, of course.
From the paper: "On the other hand, the SMBH mass (MBH) estimated from broad Hα is ∼ 4 × 10^7 times of solar..." So, looks like each of them is about 40 million solar masses. Other methods estimate 2 × 10^8, so 200 million. Two galactic nuclei are about to be smashed together!
Depends on where it is located for line of sight. If it's on the other side of the center of our Milky Way galactic core, then it won't be visible in visible light (awkwardly stated). The overall brightness and/or the thick bands of dust prohibit us from seeing some things in the visible spectrum on that side of the galaxy. However, some things can be viewed with other wavelengths.
Any time "imminent" is used in astronomy, you have to remember 1 million years is imminient when speaking about the universe. So for them to say "within 3 years" that's like go get the popcorn, you don't want to miss it level warning!
In fact, 3 years is too lucky that I must predict this is a false alarm. https://www.science.org/content/article/crash-titans-imminen... reports "Fabian says the chance of such a merger taking place so close to Earth in any given year is one in 10,000" and evidences presented don't seem strong enough to overcome 1:10,000 prior.
Meh, some lucky bloke eventually wins the powerball too. In our lifetime. Multiple times in some cases, but definitely different winners sometimes weekly. The odds of winning the lottery are a lot higher than 1:10,000.
The universe is close to 14 Billion years old. 1:10,000 is like nothing to the universe. There are several orders of magnitude stars in the universe that you could have 1:10,000 events occur daily. You as a member of the very johnny come lately human species (in terms of the universe's age) might feel like 1:10,000 seems high.
I mean, I support scratching this particular lottery ticket, because unlike lottery whose reward (money) is fungible, if it pays off we will get information we won't get any other way. But we shouldn't expect to win, that's all I am saying.
You could say "it's already happened" as a first approximation but this isn't really true because the statement implicitly assumes there is some kind of universal "now" that can be used as a reference point for timing things.
No such universal "now" exists. That's why the question "What's happening right now on Mars?" makes no physical sense. "Now" is a function of both when and where you're standing.
The question "What's happening right now on the other side of my living room?" also doesn't make any physical sense. But the difference between reality and our perception of it is less easily detectable in that case.
Incorrect. Relativistic differences in simultaneity between observers have nothing to do with light travel time between them and everything to do with different velocities. The other side your living room, and even the other side of the galaxy, is moving close enough to the same speed that simultaneity is perfectly well defined between them. So we can confidently assign times in the past to events based on what we see in the present, in the knowledge that they will be consistent with times assigned by other observers in different locations at the same speed.
The only wrinkle in the scenario of a distant galaxy is cosmic expansion inducing a different reference frame by causing motion relative to Earth. However, if the redshift isn't more than a few percent then the time dilation won't be either, so we can be pretty sure it will be in the past by any definition that isn't moving a fair fraction of c relative to us.
Don't confuse light travel time with relative simultaneity. Relativity does weird things to time but that's not one of them.
I agree that a reference frame that has about the same velocity as the stuff you care about is in some sense privileged. But the fact that we haven't seen the merger happen yet means that it's outside our light cone, which means there exists a reference frame where the merger hasn't happened yet.
that is to say, t_{this_coversation} < t_{merger}, in that frame.
It is not too strong. GP specifically claimed that simultaneity depends on "where you're standing". This is wrong in all reference frames.
As for timing of distant events, GP didn't make any reference to other reference frames at arbitrary velocity, only different positions. In our reference frame, which they were implicitly talking about, the merger (assuming the prediction is correct) was in the past, unambiguously.
There is a universal now. Just because you are in a different location it doesn't change what now is. We have clocks all over the earth synced close to each other depsite being located in different places. While physically it may be impossible to perfectly sync clocks in theory we could have theoretically synced clocks.
I don't think this is true. General relativity says that time slows down under greater gravitational forces. This has been experimentally proven. Therefore clocks at different elevations run at different speeds.
Yes. In addition, Special relativity says clocks moving faster through space tick slower than clocks that move more slowly.
So let's say you're a GPS satellite. GR says your clock ticks too fast because you're farther from the center of the earth's gravity well than the wristwatches of people on the surface.
But SR says your clock ticks slower than a wristwatch on the surface because you're whizzing through space at ~15,000 km/hour.
Which is right? Both. And they do not exactly cancel each other out (in general). So both GR and SR have to be taken into account to make GPS satellites produce accurate locations and times.
You can refer to it differently, but time progresses at different rates at the different places. So in your example, physical processes (i.e rusting, aging) at place B happen 2X as fast as those at place A.
>but time progresses at different rates at the different places.
What's the problem? We can still have a now defined as I mentioned above. t1=t2=0 at the start. Now when t1=x for place A will refer to when t2=2*t1 at place B.
"the distances and even temporal ordering of pairs of events change when measured in different inertial frames of reference (this is the relativity of simultaneity); and the linear additivity of velocities no longer holds true."
>the distances and even temporal ordering of pairs of events change when measured in different inertial frames of reference (this is the relativity of simultaneity)
I'm not saying to use different frames of reference. I am saying to use a single universal frame of reference.
If you think about the amount of time it takes to get information from Mars to Earth, it would be similar but on a much bigger scale. It takes somewhere around 20 mins one way for Earth/Mars communications depending on oribital positions. By the time we received the confirmation that landers on Mars were safe, the lander has already had a cup of tea.
The lander wasn't in paused motion so that everything times out with us on Earth. Same concept with deep space objects. What we see is the information as it was when it left. To see what happened just now, we'll have to wait another few million years.
So information is relativistic I first thought, but independent causal actions are not. But that doesn’t explain that different frames can have different experiences of time.
I shouldn’t read too much about relativity before my morning coffee.
Made me chuckle. Reading the title I was half sure this was about galaxies, it could have easily been a "merger" of "binaries" from different companies lol
I've been wondering about the "last parsec problem" ever since I read about it but this prompted me to look it up. Turns out the reason it's actually possible for black holes to actually merge instead of just orbiting each other forever is "dynamical friction" (basically as a black hole moves through a bunch of stars or other masses, its gravity pulls them inwards so that the stars it's already passed tend to be more directly behind it than the stars in front of it, so the net force on the black hole is backwards.)
That is part of it, but as the orbit shrinks, relativistic effects start to become the dominant source of orbit decay.
The most striking demonstration of this effect is what happens around the photon sphere (3/2 the radius of the event horizon of a non-rotating black hole. The orbital velocity at this radius is the speed of light. Consider the two body problem, of a single mass interacting gravitationally with the black hole. If this mass crosses the photon sphere from the outside, it will inevitably spiral into the event horizon. If the mass crosses the photon sphere from the inside, it will either escape to infinity proceed to cross it again from the outside (and subsequently spiral into the event horizon).
The more general phenomena is orbital decay that happens in any 2 body problem under general relativity. From a conservation of energy standpoint, the massive amounts of energy contained within gravitational waves come from the release of gravitational potential energy as the two orbiting objects fall towards each other.
Not necessarily. Besides, if that were the case, you would lose the ability to say you've learned anything at all... which, sadly, is also a self-contradiction. Only someone who knows can make such statements, another self-contradiction, so they wouldn't say them either. If you look in practical cases, people who really master a subject don't seem to have many questions left at all. The real problem is humans have not mastered physics yet.
That's like saying you took the first step up a ladder so there's no point in continuing to the next step. That just doesn't follow. Now, you just know you need to know more. The unknown unknowns become the known unknowns so you can learn to make the unknowns known.
I am saying the precise opposite of that. Saying that you, at your supposed low level, know that you only get more questions the more you learn, is exactly such a statement as you are claiming I am making. From another perspective, the statement sounds like an excuse for not reaching a higher level of mastery that the person admits they don't know humans are capable of. It's a self-contradiction. Thanks for all the downvotes, y'all! Definitely didn't trigger anyone.
Not to jump to conclusions too much but I've recently been seeing a lot of "fake science news" out of China lately. Seeing gelatin on the moon, seeing a "house" on the moon, and now this.
After reading this article, it sounds like another group of researchers are throwing shade saying there's some jumping to conclusions based on very little observational data.
It's funny to see the competitive nature between groups.
The one thing I took from this article though was that the instrument we have built specifcally to detect gravitational waves won't even be effective for this level of event as it is "tuned" for different type of events.
Gravity wave detectors are sensitive to ranges of frequencies, just as electromagnetic wave detectors are. For instance, LIGO is sensitive to gravity waves in the range of 7kHz down to 30Hz. The gravity waves from this merger would be at far lower frequencies/longer wavelengths.
I understand the rush to be first. I was going with funny haha not funny strange as the groups from competing theories just can't stand it when the other theory gets some spotlight attention. I can't imagine picking a theory and making your entire life about proving/solving that theory only to find out you were wrong! Not like move a decimal over wrong, but up the wrong tree wrong.
If you mean "Catastrophic Anthropogenic Global Warming", then that's probably the least bad way to be wrong. Because when you're wrong at least the world will be better off. Like betting against your own team: if they lose you win and if they win you don't mind losing.
Just the other day in another unrelated thread, someone posted a youtube video that introduced me to a new channel. Just today I was watching one of the videos that discusses black hole mergers:
Some caution is warranted here. AGN have “red-noise” variability that can produce signals that look periodic. There have been lots of similar claims that fizzled. Thankfully this one will become clear soon.
The headline looked like something taken from Greg Egan's Diaspora, but what happened there was far closer and with just neutron stars. Anyway, it was pretty dramatic for the not-so-nearby solar systems,
I wonder what means an event like this for good part of the galaxy where it happens.
It's not like there hasn't be warnings for like millions of years. However, just like on Earth where there are people with plenty of advanced notice about hurricanes that decide they are just going to ride it out, I could see some ignoring these warnings as well.
"I've lived next to this volcano/merging black holes for my entire life, as my family before me. Nothing has ever happened." Until it does.
“There’s no point in acting surprised about it. All the planning charts and demolition orders have been on display at your local planning department in Alpha Centauri for 50 of your Earth years, so you’ve had plenty of time to lodge any formal complaint and it’s far too late to start making a fuss about it now. … What do you mean you’ve never been to Alpha Centauri? Oh, for heaven’s sake, mankind, it’s only four light years away, you know. I’m sorry, but if you can’t be bothered to take an interest in local affairs, that’s your own lookout. Energize the demolition beams.”
> SDSSJ143016.05+230344.4 (hereafter SDSSJ1430+2303) is known as a Seyfert 1 galaxy at redshift 0.08105
https://astro.ucla.edu/~wright/CosmoCalc.html says this galaxy is ~1.1 Gly, so "not exactly close" whatever that means on a cosmic scale. Intriguingly, this event took place when life on Earth barely existed at all...
Edit: at 1,5x10¹¹ solar masses, the galaxy is not at all small (and neither are the BH involved!!!) it's in the same ballpark of the Milky Way.
Not sure what the distance is to the source, but it is good to realize that us observing the event is only imminent; the event itself happened already many years ago (thousands, millions?) and the signal has been travelling all those years to its very curious audience.
Do you own stock in any industry near the galactic core of SDSSJ1430+2303? You might want to sell that while we're still outside the causal lightcone. Unfortunately this is probably all mostly priced in by now.
The opposite of HFT is ULFT: stock trading on a gigayear timescale outliving the typical planetary civilization. Its biggest enemy is inflation -- meaning cosmological inflation, that nasty phenomenon tearing the universe apart and doing a number on intergalactic shipping indices. To quote an extremely recent earthling philosopher: intergalactic trade grows strong when elderly hominids plant {untranslatable #32} in whose {untranslatable #993} they know they shall never {untranslatable #440}.
It's 1.2 billion light years away, and the problem seems to be about how to actually measure things. And not worrying about gamma radiation bursts wiping us out along with our local galactic neighborhood or the GPS system failing.
Between 100 days and 3 years we will record what will be the single largest energy release we have ever recorded.
To give an idea of our records so far: our detection of black hole mergers around the 100-150 solar masses scale are just behind a couple gamma ray bursts as the single largest energy release ever.
How big are the black hole mergers around 150 solar masses and the two largest gamma ray bursts?
The energy release converted the mass of between 1-6 solar masses into energy.
With black hole mergers this energy release/conversion is in the form of gravitational waves that we then detect!
So imagine the sun, times 6, every atom, converted into that energy. That’s what we have already recorded.
This predicted one is not even in the same ballpark. Those 1-6 sun matter into energy conversions are ants compared to what’s coming.
These supermassive black holes are thousands to tens of thousands of times the mass of our sun. (Not sure if the ones in this paper are in the billion solar masses class. Yes they do exist)
This event will convert the mass of perhaps a hundred or a thousand suns worth of matter into energy in an instant. (Not sure if the paper gives any accurate predictions I’m lazy!)