back to article Years after we detected two neutron stars crashing into each other, we're still picking up X-rays. We don't know why

After a thousand days of observations, the continuing X-ray radiation from two neutron stars smashing into one another has left astronomers puzzled. The collision, code-named GW170817, was picked up by our planet's LIGO and Virgo gravitational wave detectors in mid-2017. The incredible crash, some 130 million light-years away …

  1. Pascal Monett Silver badge
    Boffin

    "the emissions are 100 billion times brighter than those from the Sun"

    So they're getting x-rays from a merger that are stupendously bright. Did they point an optical telescope there to see if anything was visible ?

    How about infra-red ? If the two neutron stars don't have nuclear fusion, they should certainly be radiating heat like crazy.

    Of course, if they've become a black hole, then the source has to come from the jet, but couldn't the jet be visible if it 10,000 billion kilometers long ?

    EDIT : after a short search, I found this article that details nicely all the important things about this merger, and there are many. But nothing on the jet.

    1. UCAP Silver badge

      Re: "the emissions are 100 billion times brighter than those from the Sun"

      Yes, they did get an optical counter-part - it was called a "kilo-nova" (like a supernova but much, much smaller). It was visible for about 3 weeks before it faded, and was observed using every telescope they could beg/borrow/steam observing time for, and in just about every spectrum they could utilise.

    2. Anonymous Coward
      Boffin

      Re: "the emissions are 100 billion times brighter than those from the Sun"

      Surprisingly, while the proposed jet is too small to resolve it might in due course become large enough to resolve optically. Assuming green light (500nm) then, if we were looking at it from the side, you'd need a 75 metre telescope, which is much bigger than anything we have. But if it was ten times bigger it would be resolvable.

      However I think that if we're seeing stuff from it that means it's pointing approximately at us which would make life much worse.

      But more significantly we die see light from this thing, but it's now faded. What we're seeing now is presumably extremely non-thermal, so just because we see x-rays does not mean there will be a huge amount of lower-energy radiation (and indeed, since we're not seeing any, we kind of know it's a lot less luminous at lower energies I think).

    3. Charlie Clark Silver badge

      Re: "the emissions are 100 billion times brighter than those from the Sun"

      The article isn't brilliantly written. For "bright" read "intense". And, I think, for "jet" read "jet of material". This would allow us the work out the speed of the explosion, Reg Standard Units, which sounds pretty damn impressive: life around the explosion that somehow survided the x-rays would certainly have been knocked out by the explosion!

      1. HildyJ Silver badge
        Boffin

        Re: "the emissions are 100 billion times brighter than those from the Sun"

        The event was bright, in the common parlance, in the visible spectrum. In astronomical terms it was both bright (referring to the amount) and intense (referring to the energy).

        From what was described, the jet referred to was a jet of photons, from gamma rays on down, and not a jet of material (like a coronal mass ejection).

        Life, if any, around the two stars would have been wiped out long ago when each of the stars formed. In any event, the gamma rays would be far more inimical to life than the xrays.

        My bet, for what it's worth, and it's not worth much, is that the collision left a remnant which boffins can study.

        1. Anonymous Coward
          Boffin

          Re: "the emissions are 100 billion times brighter than those from the Sun"

          No, it's a jet of matter, emitted at relativistic (probably very relativistic) speeds, but it's matter: we're seeing (or were seeing) radiation emitted by the jet.

          You're right that 'bright' is the common term in astronomy though: the article wasn't sloppily written, it was just using the terms in the way astronomers use them, which I think is fine.

          1. Charlie Clark Silver badge

            Re: "the emissions are 100 billion times brighter than those from the Sun"

            Yep, we can't have seen both the x-rays and gravitational waves and have a "jet of photons" spread only as far the size of the solar system.

    4. Cynic_999 Silver badge

      Re: "the emissions are 100 billion times brighter than those from the Sun"

      Don't forget to factor in doppler shift. What started as visible, X-ray, infra-red etc. may not be in those bands when we observe them.

      1. KarMann Silver badge
        Boffin

        Re: "the emissions are 100 billion times brighter than those from the Sun"

        Not really. You may think it's a long way down the road to a galaxy 150 million light-years away, but that's just peanuts to cosmological redshift. It's only redshifted by about 1%, which is certainly enough to put emission/absorption bands in a noticeably different place, but isn't anywhere near enough to change gamma rays to X-rays, X-rays to UV, UV to visible light, etc. You'd probably need something like a 20% redshift to see much of anything changing bands like that.

        1. xeroks

          Re: "the emissions are 100 billion times brighter than those from the Sun"

          DNA reference <nods>

  2. Version 1.0 Silver badge

    We know we don't know

    This is a good illustration of the history of knowledge - go ask politicians or your average Joe and they will tell you that we know everything about the universe. But if you ask scientists they will tell you that there are some interesting observations and theories about the universe that suggest we have some good ideas about what might be out there.

    400 years ago an apple (fruit not a phone) fell on Issac Newton's head and started a new view of the universe leading to a lot of new knowledge, so I think that we can assume that our current view might change in the next 400 years ... perhaps the kids in school will be laughing about a discovery back in 2024 when a scientist dropped his phone and suddenly thought that the light speed limit only applied to the visible universe?

    1. Paul Kinsler Silver badge

      Re: the light speed limit

      Just to clarify this, it isn't a "light speed limit", although it certainly has that side effect. It's a limitation of the spacetime in which the light travels.

      Thanks for the heads-up, though. But should I be dropping hints about wanting a non-slip phone case just before Xmas 2023, ... or instead making sure that my phone gets inexplicably covered in lubricant during the New Year celebrations?

    2. Lars Silver badge
      Alien

      Re: We know we don't know

      "and started a new view of the universe "

      I would for "the view of the univers" choose:

      Galileo di Vincenzo Bonaiuti de' Galilei[2] (Italian; 15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath, from Pisa.[3] Galileo has been called the "father of observational astronomy",[4] the "father of modern physics",[5][6] the "father of the scientific method",[7] and the "father of modern science".[8]

      Galileo studied speed and velocity, gravity and free fall, the principle of relativity, inertia, projectile motion and also worked in applied science and technology, describing the properties of pendulums and "hydrostatic balances", inventing the thermoscope and various military compasses, and using the telescope for scientific observations of celestial objects. His contributions to observational astronomy include the telescopic confirmation of the phases of Venus, the observation of the four largest satellites of Jupiter, the observation of Saturn's rings, and the analysis of sunspots. ".

      And going further back in time is no problem as we have had this capability and curiosity about our surrounding from the beginning of time and the sky has always and in every society played such an important roll.

      Remember how all weekday names come from the sky.

      Monday is derived from Old English Mōnandæg and Middle English Monenday, originally a translation of Latin dies lunae "day of the Moon"

      Tuesday derives from the Old English "Tiwesdæg" and literally means "Tiw's Day". Tiw is the Old English form of the Proto-Germanic god *Tîwaz, or Týr in Old Norse.

      Wednesday is derived from Old English Wōdnesdæg and Middle English Wednesdei, "day of Woden", reflecting the religion practised by the Anglo-Saxons, the English equivalent to the Norse god Odin.

      Thursday is derived from Old English Þūnresdæg and Middle English Thuresday (with loss of -n-, first in northern dialects, from influence of Old Norse Þórsdagr) meaning "Thor's Day". It was named after the Norse god of Thunder, Thor.

      Friday comes from the Old English Frīġedæġ, meaning the "day of Frige", a result of an old convention associating the Germanic goddess Frigg with the Roman goddess Venus, with whom the day is associated in many different cultures. The same holds for Frīatag in Old High German, Freitag in Modern German, and vrijdag in Dutch.

      The name "Sunday", the day of the Sun, is derived from Hellenistic astrology, where the seven planets, known in English as Saturn, Jupiter, Mars, the Sun, Venus, Mercury and the Moon

    3. Anonymous Coward
      Anonymous Coward

      Re: We know we don't know

      “It may be that our models are somehow incomplete and do not fully capture the complexity of these extreme phenomena, or we may be seeing something else," Troja said.

      Honestly, Troja could have stopped after "incomplete". All models are incomplete. A hundred years ago, we had what is now called classical mechanics, but it was incomplete. 70 years ago our subatomic particle model was incomplete. While not a betting man (I only put money on a sure thing), I'd happily wager that our quark model is incomplete. As for our understanding of the physics of the collision of massive objects an unimaginable distance away, being observed strictly through telescopes (light of various frequencies), I'm sure it's incomplete. A good starting point, but incomplete.

      Having known a few scientists, I suspect he's tickled pink to have discovered that the current model has a flaw, and will happily spend years figuring out what that flaw is and how to fix it. Very good work on his part.

    4. Anonymous Coward
      Anonymous Coward

      Re: We know we don't know

      That's not really true though.

      You have 1000 papers peer reviewed forming a chain of knowledge.

      There is a dumb thing at paper 500 that everyone knew at the time was a dumb placeholder, but the problems with it were ignored.

      But 500 teams have built on that flaw.

      It is impossible then to fix that problem because 500 teams work would need to be wrong for 1 teams work to be right.

      Instead a sort of mysticism builds up so that those 500 papers are based more on faith than reality.

      As the contradictory evidence grows, so the faith becomes stronger, the need for those 500 teams to save 'science' gets stronger and stronger. They believe more. More denial. More faith!

      "and suddenly thought that the light speed limit only applied to the visible universe"

      A magic constant that is universe wide?

      n [space units] per [time unit]

      But if space is stretched then so is matter, so measure it against matter will always get the same result if the matter and the light are in the same local space, even if space is stretch. We already know space isn't even and uniform. Yet the constant remains.

      So now we remove the space unit, we have n per [time unit]

      So lets set out time unit as 1.

      Light comes from matter (e.g. an electron drops a shell or two and emits a photon), so the speed of light must be linked to the speed of that process. The two things are linked somehow.

      Speed up time and we speed up matter.

      Light travels ~1 [something] per matter's motion of ~0 [something].

      i.e. All matter is close to local 'stationary', ~0, all light is close to some ~1 relative to that matter. So whatever could an electro magnetic wave be travelling over? Something that has 0 and 1, more damn integers?

      One might wonder.

      So now our magic constant isn't magic or a constant, its just a constant ratio relative to our measurement. If we measured light in one context relative to another, we'd get a different result.

      So do we ever measure light at a different velocity? Well, yes when it goes through glass, we measure it from the outside of the glass. Is it in a different matter context to the one we are measuring from? The light is inside the glass, and we are outside. So why is the ~1 unit in that 'glass' matter context different than the ~1 unit in our 'air' context?

      And then there's the straight line.

      If our space is more dense on the left than on the right, then light swings to the left.

      And so does matter moving over the same field.

      "straight" is whatever direction the light takes, but only for the matter moving the same as the light. To an outside observer it moves according to the medium it is travelling through. But then we know this right? Its' literally the basis of everyday lenses. We literally see it change direction as it moves from one local field to the next, as long as we're outside one of those fields.

      So, are there multiple paths across space that would go from A to B taking a different number of N units of time? i.e. smeering out the event over time?

      Well their *could* be, because we do that with lenses, light can take two paths and end up at the same place at different times. But to suppose that for space you have to think space you'd have to see space as not uniform or even. For that you'd have to be outside it, like being outside the lens as the light passes through it.

      1. Paul Kinsler Silver badge

        Re: You have 1000 papers peer reviewed forming a chain of knowledge.

        It's not a chain of knowledge, it's more of a network or mesh. It might have some single point of failure which compromises the whole thing, but more likely in most places it gives good results because the "bad" result is out-weighed by nearby "good" ones. Persistent inconsistency will very likely be spotted and investigated.

      2. Anonymous Coward
        Boffin

        Re: We know we don't know

        So, are there multiple paths across space that would go from A to B taking a different number of N units of time? i.e. smeering out the event over time?

        Yes, of course there are: that's called gravitational lensing. It was first observed by Eddington 101 years ago, and it's one of the great early tests of general relativity.

        I like your idiot conspiracy-theory claim that scientists are all somehow too embarrassed to point out the obvious flaws in their experiments – flaws which, of course, an anonymous crank in the comments column of an IT website is the only person smart and brave (but, you know, not brave enough to put their name to their comments, eh?). The person who points out that flaw wins a fucking Nobel prize and is has their name in the history books as the person who finally sorted out that relativity was wrong (something, in the case of GR, that we all know must be true and that thousands of people have trying to sort out for fifty years). But no, the might of the physics establishment is busy suppressing this, right? Just like they suppressed the person who pointed out, in 1964, that an obviously absurd mathematical toy idea was in fact something that actually happened ... oh, no, they didn't, did they: he just won a Nobel prize for that.

  3. John Jennings Silver badge

    Its obvious

    Its a navigational beacon to warn intergalactic motorists of the collision.

    Someone forgot to lift the cones (again!)

  4. Oh Matron!

    So here's a thought:

    In the future, could we detect supervova ahead of time becase we detected their gravity wave first?

    What is the speed of gravity? (Not what is the acceleration of mass due to gravity)

    1. james 68

      Re: So here's a thought:

      With or without racing stripes? Everyone knows adding racing stripes will make anything faster.

    2. Anonymous Coward
      Boffin

      Re: So here's a thought:

      It's the speed of light, so no. The speed of light is really the speed of causality: it's the fastest way any information about an event can get between any two points (disclaimer: as far as we know (disclaimer to disclaimer: but if this turns out not to be true we get to build time machines pretty easily, which is a very strong argument for it being true)).

      In fact, rather amazingly the way to get early warnings about some supernovae turns out to be to use massive particles which travel strictly slower than the speed of light. In a core-collapse supernova, then as the star collapses it spits out a really enormous amount of neutrinos. Because neutrinos barely interact with anything they come straight out from the core of the star, while photons undergo lots of interactions on the way out. Neutrinos, because they're so light, also travel very, very close to the speed of light. What this all means is that the neutrinos from core-collapse supernovae can reach us several hours before the light does. This works only for relatively close events – I'm not sure when the light catches the neutrinos, but the neutrino flux will also drop below detectability at relatively short ranges as they're so hard to detect.

      This was observed, retrospectively, for SN 1987A. There's now a network of neutrino detectors called SNEWS (supernova neutrino early warning system) whose purpose is to try to give optical telescopes enough warning to look for the start of the optical event by seeing the neutrinos a few hours before. I don't think it's seen an event, yet.

      1. Charlie Clark Silver badge

        Re: So here's a thought:

        The speed of light is really the speed of causality: it's the fastest way any information about an event can get between any two points

        Well, quantum entanglement appears to be faster in some situations but also prone to destroying the information… One of the reasons why it's so hard to align quantum theory and relativity but it wouldn't surprise me if someone at some point came up with a way, along with a more fiendish problem because that's how quantum stuff tends to work. Or maybe we'll stumble upon tachyons only to find them useless for this sort of thing.

        1. Anonymous Coward
          Boffin

          Re: So here's a thought:

          I hate this myth. Quantum entanglement is weird, but it's not weird in that it happens instantly. It's trivial to see this. I give you a box, and keep a box to myself. You go far away. I open my box, which has a left shoe in it: if you open your box you will find a right shoe, and you can do this while you are outside the light-cone of me opening my box.

          This is exactly the same case as happens with quantum entanglement, and as with quantum entanglement no information is transmitted faster than c. But this is just shoes in boxes, there is no magic QM here. Entanglement is weird but it's not weird in this way. Entanglement is weird because you can show that before you opened the box it didn't contain either a right shoe or a left shoe.

          (Also, QM and relativity work fine: QM and gravity don't.)

          1. Anonymous Coward
            Anonymous Coward

            Re: So here's a thought:

            Your explanation of QE is not the current claim for QE.

            You have 5 boxes given to each of 5 people. They each open box 1, you select the subset that have the same shoe in box 1. Declare those two people successfully entangled, then open the other boxes and they contain the same types of shoe in each. Spooky distance effect that happens faster than light!

            The type of shoe is claimed to be determined when person 1 opens each box and thus measures each shoe, which in turn dictates the type of shoe in persons 2 corresponding box. Until that measurement is made, the shoe is not defined. The type of shoe in box 1 is claimed to be completely independent to the type of shoe in box2, box3...box5.

            That entanglement needs to be both faster than light and yet somehow not.

            " and as with quantum entanglement no information is transmitted faster than c"

            Of course in reality, the properties are claimed to be independent and are not.

            e.g. red shift shows that the frequency and relative motion of the detector are not independent.

            Turn polarization into circular polarization via a crystal and you've determine those properties are related.

            Rotate that crystal, you get a different result confirming that vertical and horizontal polarization must be interconnected.

            So Box1 to Box5 are not independent, there is a relationship between the shoes.

            And red shift amount depends on the motion of the detector, not just the light, so you can determine you're not measuring the light, you're measuring the net interaction between the light and the detector for that experiment.

            Likewise a crystal that turns 45 degree polarization into clockwise circular polarization, depends on the motion of the crystal as to the resulting spin. So another property of detector and detected that the net effect between the two.

            Star X measured by Star Y has a red shift, is Star X moving away from Y, or is Star Y moving away from X, or some combination of the above?

            Multiple combinations of properties produce the same net effect between the detector and the detected. As you match up the shoes, you are determining the relationship between detector and detected.

            A red left shoe in box 1, narrows it to one net interaction. The same blue right shoe in box2 narrows it further, till the relationship is established and the remaining shoes are the same.

            So the properties appear to be independent, yet they are not.

            [This you correctly assumed when you assumed that the boxes contain a pair and if one if left shoe the other must be right shoe! i.e. your attempt to explain QE correctly points to the error in QE!]

            So if you open enough boxes to determine that person 1 and person 2 have the same net different between their detector and their box set, you can then open the remaining boxes and they will be the same because the content of the boxes are connected.

            So of course QE doesn't work as claimed. YOU DO NOT SET THE CONTENT OF THE SHOE BOX WHEN YOU OPEN THE BOX!

            Except in this case the content of the box is always some sort of motion. Spin, oscillation rate, oscillation axis, all properties are motion, all of these independent properties are types of motion. So its much more obvious when you realize they're all motion.

            What would a form of motion that ends up not moving across space be called? We'll lets label it mass, just so you can realize that matter is another form of motion, and must also be related.

            1. Anonymous Coward
              Boffin

              Re: So here's a thought:

              Your explanation of QE is not the current claim for QE.

              That's because I did not explain quantum entanglement, nor attempt to. Instead I gave an example of a purely classical experiment by which you can become aware of bits of information which are not in your past light-cone, thus demonstrating that that's not the weird thing about entanglement.

              1. 7layersdown

                Re: So here's a thought:

                But all the information about the shoe in your box and the inference you may draw about the contents of the other box are in your past light-cone; the opening of the other box in this example does not affect the contents of your box. You know what the other person would expect to find if they open their box. You do not know if they have already done so.

                1. Anonymous Coward
                  Boffin

                  Re: So here's a thought:

                  Right, and that's exactly the same as the case with quantum entanglement: the system is prepared in our mutual past, and until I communicate to you what measurements I did you can't tell what information I was trying to communicate, so no information ever travels outside the light cone. That's all I was trying to say, and it's a very uncontroversial result.

          2. Charlie Clark Silver badge

            Re: So here's a thought:

            Thanks for the additional explanation and thought experiment. That you can't use entanglement for the transmission of information was my point, even if the effects appear to be faster than the speed of light.

            1. Anonymous Coward
              Anonymous Coward

              Re: So here's a thought:

              Yes, sorry my 'I hate this myth' comment was not aimed at you: I should have made that clearer. I wasn't trying to be rude, although I probably did manage to be.

              (Unlike our AC crank: quite happy to be rude to them.)

        2. bombastic bob Silver badge
          Devil

          Re: So here's a thought:

          quantum entanglement appears to be faster in some situations

          Quantum entanglement seems to follow a different set of rules [as I understand it].

          Gravity should follow the same rules of space/time as does both light and EM fields. But yeah, quantum entanglement is something else entirely.

          NOTE: if you use super-strong gravity + EM (and maybe light) to create some kind of warp bubble, the rules of physics would apply normally within the bubble, and outside of the bubble, but not at its border, and so moving the bubble would move you along with it "faster than light", or so the theory goes. Some physicist from Mexico came up with a really good description of how it's done a decade or so ago.

          1. Anonymous Coward
            Boffin

            Re: So here's a thought:

            You understand entanglement, or at least you're correct that gravity (as we understand it) is a classical – non-quantum – thing. Obviously a correct theory of gravity will be quantum, but we don't have one: we only have the classical limit theory, which is GR.

            The thing you describe in your last paragraph is the Alcubierre drive. The big significant thing about it is that it requires negative energy density, which really means negative mass. I think people are pretty confident that negative mass isn't possible, and really the Alcubierre drive is something which makes us more confident of this. You can use an Alcubierre drive to create what are called 'closed timelike curves', which is the GR terminology for being able to get into your own past, aka building a time machine aka violating causality.

            So this is getting closer to being a nice thing: in particular if you could show that in order to violate causality you required negative mass, then you've reduced the problem of showing that causality is not violated to that of showing that negative mass can't happen.

            A lot of this stuff is like that: there are various absurd things (negative energy, causality violation, singularities) which everyone kind of knows are implausible but we can't yet say why. So if we can come up with results that show that thing a either implies thing b, or is equivalent to thing b, then we know that if we can show that thing a can't happen we've solved the thing b problem too (or alternatively if we can show that thing a can happen we know we're in bad trouble, which would be even more exciting – in this case if it turns out that negative energy is possible we know that causality can be violated and time machines are possible).

            Of course people then glom onto the Alcubierre drive because it says 'drive' (and sometimes even 'warp') and start saying that this means that we've discovered FTL travel, because they desperately need FTL travel to be true so all their SF can be true, or at least less silly. I don't really understand this: I read SF, including SF with FTL travel, but I understand that the 'F' stands for 'fiction'.

            1. bombastic bob Silver badge
              Devil

              Re: So here's a thought:

              there are various absurd things (negative energy, causality violation, singularities) which everyone kind of knows are implausible but we can't yet say why

              yeah good stuff, but keep in mind that for every particle there is an anti-particle, except maybe for gamma [which you could call 'energy' I suppose]. gamma is the result of the annihilation of a particle and an anti-particle. However, if anti-particles are actually particles moving backwards through time [maybe disproved, maybe not] the need for anti-energy wouldn't be there - only anti-time.

              And... consider the multi-verse interpretation, where causaility is not a fixed thing. A paradox is resolved through time travel the moment the time traveller "arrives", because a new universe gets created in the quantum event of his arrival. Or something like that.

              I've actually considered a sci fi plot surrounding that. Man invents FTL drive, and after testing it, arrives in an alternate universe where history is messed up, like the Nazis won WW2 or it's still Rome in modern day, or everyone's a communist because the USSR won the cold war. Many 'Sliders' plots were like this. Anyway, the protagonist must now use his knowledge of history, discover how to move backwards in time, and find the point at which his arrival screwed things up, and then "fix it" so he can get back to his own time line. Not a new concept, really, but a new twist on an old trope. Could become an entire series... [and I can think of many that had history as a plot device, from Dr. Who and Time Tunnel to Sliders and Highlander]

              (but I guess this article is kinda old now, and maybe nobody will see this...)

              1. Anonymous Coward
                Boffin

                Re: So here's a thought:

                [...] for every particle there is an anti-particle, except maybe for gamma [which you could call 'energy' I suppose]. gamma is the result of the annihilation of a particle and an anti-particle. However, if anti-particles are actually particles moving backwards through time [maybe disproved, maybe not] the need for anti-energy wouldn't be there - only anti-time.

                Well, what you need is particles with negative mass (rest mass), really. And we know because we do experiments in accelerators that antiparticles have positive rest mass (for instance LEP, which was the predecessor of (and lives in the same tunnels as) the LHC, collided electrons and positrons, and simply would not have worked at all if positrons had negative mass).

                There's one possibility which is that antiparticles feel gravity in the opposite sense – so they fall upwards really. We strongly suspect this is not true, not least because photons are their own antiparticles, and we know that photons/antiphotons both therefore feel gravity in the same sense as each other. For massive particles we don't know as far as I know, yet. However experiments are being done (the problem is that gravity is terribly weak and collecting enough antimatter and keeping it isolated for long enough is very hard). As far as I know those experiments don't yet have conclusive results although the indications are that antimatter and matter both feel gravity the same way.

                However even if antimatter fell up this doesn't really help – or, rather, it does help, a lot, but not in the obvious way. The reason is that it's a strong assumption of GR that inertial mass and gravitational mass are the same. But if antimatter falls up, then the gravitational mass of antimatter is negative while its inertial mass is positive. This would mean that GR is wrong. And not just a little bit wrong but completely and utterly wrong. But if GR falls then the Alcubierre drive falls with it. Of course somerhing much more exciting would probably rise in its place, which would be very cool.

                Incidentally this is one of the reasons why the conspiritards who turn up here and say that physicists are all suppressing their clever theory involving vibrations and spheres or something are so silly. If physicists were all conspiring to suppress information that might overturn major theories of physics they would not be doing these experiments on antimatter, and still less would they be doing them given that everyone strongly suspects that the results will be that antimatter has positive gravitational mass. But these experiments are being done, with funding etc. There is no conspiracy (at least not in physics).

                (but I guess this article is kinda old now, and maybe nobody will see this...)

                I come back to look at old article comments!

                I like your scifi idea by the way. Have you read a story called 'by his bootstraps' by Heinlein? There are many scifi time-travel-paradox stories but that's one of m favourites (disclaimer: have not read it since, probably, the late 1970s, it may not be as good as I remember).

      2. bombastic bob Silver badge
        Boffin

        Re: So here's a thought:

        The speed of light is really the speed of causality: it's the fastest way any information about an event can get between any two points

        That's a nice summary!

        One of the explanations (in the article) of the 3 years' of X rays is the creation of a 3rd neutron star. In short, they're suggesting that, like a nuclear reaction, on a macro scale the neutron stars collided to form a "massive unstable star-particle" which then "fissioned" into multiple parts... and when you study how nuclear fission actually works, this makes for a VERY interesting analogy. Keep in mind a neutron star is a bunch of neutrons held together by massive gravity, similar to a black hole. But inside a black hole, matter is even denser and has a "6th state", sort of a non-particle "mush" containing everything that WOULD be atoms and neutrons and quarks and electrons and all of that, except it's so dense it just "mushes" and all of the borders between things go away. Or something like that.

        (as I understand it, there are 6 states of matter: solid, liquid, gas, plasma, gamma, and that mushy stuff you find inside a black hole - and only the first 4 states actually keep atomic structure somewhat intact)

        A neutron is (as a particle) the combination of a proton, electron, and 2 anti-neutrinos. Reason is that anti-particles and particles must balance. And so those recently-proven-to-exist neutrinos provide the anti-particles to make up the neutron. And then you crush the neutrons under high gravity, to form a neutron star, which [in theory] would really be 'neutron mush' that can still act like neutron particles [until you crush it even further into a black hole]. In a way, it's like a ginormous atom.

        NOW, you combine them in a collision, not unlike nuclear fusion. The new neutron star is unstable, and splits apart. Gamma is released, and quite possibly, additional "smaller bits" (i.e. 3rd neutron star), much like what you see in atomic fission reactions, only on a lot bigger scale.

        And that 3rd star now has too much kinetic energy, quite possibly spinning at close to relativistic speeds. It's a fair bet that gravity forced an inelastic collision, which means kinetic energy had to go someplace. I suspect that the 3rd star is spinning like hell, WAY too fast to be stable, and is slowing down by emitting gamma. [I also have to wonder whether or not the 3rd neutron star would actually be a black hole created by the collission, and the same point about kinetic energy and inelastic collisions]

        Anyway I could be as right or wrong as anyone based on the analysis here. But it would be fun to see, if we could get up close without being X-ray'd to death.

        1. Anonymous Coward
          Boffin

          Re: So here's a thought:

          One of the explanations (in the article) of the 3 years' of X rays is the creation of a 3rd neutron star. In short, they're suggesting that, like a nuclear reaction, on a macro scale the neutron stars collided to form a "massive unstable star-particle" which then "fissioned" into multiple parts...

          I can see that reading of it, but I am almost sure that's not what they are saying. The proposed 3rd neutron star is the thing that results from the collision of the first two. Really, in such a collision the result is either going to be a neutron star or a black hole: which you get depends on the masses of the colliding neutron stars, how much mass they shed during the collision, and finally the characteristics ('equation of state') of the stuff neutron stars are made from, which they describe as 'poorly understood' which I think is an understatement to put it fairly mildly.

          Depending on whether the resulting object is a black hole or a neutron star the amount of energy which gets injected into the various crud which gets flung off as jets, varies – I think neutron stars can inject more energy as they spin down. So, since they've seen emissions for longer than they expected, one possibility is that the central object is indeed a neutron star and not a black hole, and this would be interesting because it would tell us things about neutron stars I think.

          1. bombastic bob Silver badge
            Happy

            Re: So here's a thought:

            "So, since they've seen emissions for longer than they expected, one possibility is that the central object is indeed a neutron star and not a black hole, and this would be interesting because it would tell us things about neutron stars I think."

            More like 'fusion' then - and being inelastic, kinetic energy has to go someplace... and so it spins so fast that it must slow down somehow, so emits gamma [and maybe absorbs a good deal of that, too, like you suggested]. But when the neutron star absorbs it, what does it cause to happen? I was assuming that it's behaving like an excited atom, which must either emit gamma or fission to remain stable. On a macro scale.

  5. The Empress

    Space aliens and Trump colluding to steal the 2020 election. It's science.

  6. Howard Sway

    Lead astroboffin

    Not sure how a lead astroboffin could observe this. X-Rays can't pass through lead.

    1. bombastic bob Silver badge
      Trollface

      Re: Lead astroboffin

      I hate to spoil your joke, but in reality, a "tenth thickness" of a shielding material is the approximate thickness (along the path of the gamma) needed to reduce radiation levels to 1/10 of what it was. So in theory SOME X-rays will get through lead, but depending on its thickness, most probably won't.

      /me ducks rotting veggies and half-cups of liquid

  7. Dr. G. Freeman

    A theory-

    Things went bang. When that happens smoke comes out.

    X-rays equivalent to smoke when neutron stars bang into each other ?

    So, whatever is sitting there now is smouldering x-rays.

  8. Jamie 14

    Maybe they forgot to evict the Pigeons and their poop again!? It's Happened before, The receiver gave false readings! BBC Horizon, The Death Star.

    1. Anonymous Coward
      Alien

      The thing that saw these x-rays is in space, so they'd need to be SPACE PIGEONS. Which is coincidentally the name of my new band. Our first release , 'POOP', is available in all the finest record shops.

POST COMMENT House rules

Not a member of The Register? Create a new account here.

  • Enter your comment

  • Add an icon

Anonymous cowards cannot choose their icon

Biting the hand that feeds IT © 1998–2021