back to article It's all a matter of time: Super-chill atomic clock could sniff gravitational waves, dark matter

Physicists have designed super-accurate atomic clocks that may be able to detect gravitational waves and dark matter by the way those phenomena affect gravity and therefore time. The eggheads experimented with super-cooled ytterbium, a rare earth element, to measure the passage of time, and see how gravity affected it. Grav …

  1. John Smith 19 Gold badge
    Thumb Up

    Neat

    Atomic clocks are the gold standard for time measurement so the question is "What can shift the frequency of a rock solid oscillator like the frequency emitted by an electron doing a level transition?"

    Speed of movement (General Relativity) has been tested this way since the late 60's but the actual force of gravity itself is new.

    Historically it's been the case that when it seems like the science is only refining what is know that whole new areas of phenomena have opened up. IOW what the boffins list is only the start of the list that may show up.

    Well done.

    1. Version 1.0 Silver badge

      Re: Neat

      Sounds like a candidate for a Noble Prize in the future - the possibilities for this are fascinating!

      1. Anonymous Coward
        Anonymous Coward

        Re: Neat

        That is a very nobel thought.

    2. Anonymous Coward
      Anonymous Coward

      Re: Neat

      Historically it's been the case that when it seems like the science is only refining what is know that whole new areas of phenomena have opened up. IOW what the boffins list is only the start of the list that may show up.

      Yes. Give it time *cough*

    3. Andy The Hat Silver badge

      Re: Neat

      "Speed of movement (General Relativity) has been tested this way since the late 60's but the actual force of gravity itself is new."

      Is it? Time dilation due to variation in gravity has been demonstrated experimentally many times over the last 50 years ... Did they not send an atomic clock to the ISS (or as a Shuttle experiment) to do a weightless comparison some years ago?

      If this system is much more sensitive to that variation that may be new, not the experimental concept itself.

    4. ibmalone Silver badge

      Re: Neat

      Speed of movement (General Relativity) has been tested this way since the late 60's but the actual force of gravity itself is new.

      Actually, you're doing that experiment every time you use your phone's GPS

      (Sadly third hit on goggle for a search on this topic is a "general relativity is false page" that claims to demonstrate this correction is not needed. The people who believe that are welcome to design and launch their own version... so long as they promise to use no other means of navigation.)

      1. el kabong Silver badge

        third hit on google: "general relativity is false"

        I fear that too many people will support that idea, there are many people out there who refuse science, people like most most supporters of the USA's pussy-grabber-in-chief. I fear that most of them will never accept that general relativity is correct.

        1. Yet Another Anonymous coward Silver badge

          Re: third hit on google: "general relativity is false"

          It's simple enough to test for yourself, you just need a mountain, a minivan and a couple of atomic clocks

          Project GREAT

      2. RLWatkins

        Re: Neat

        About that third Google hit, you should spend some time on USENET. Take a gander at 'sci.physics' or 'sci.physics.relativity'.

        I don't read either group lately, got tired of all the you're-stupid-and-everything-you-know-is-wrong posts, but some of them are justified: the crowd of relativity-deniers who gather there beggars belief.

        What makes that all the more sad is the relative technical sophistication required even to use USENET. These are fairly intelligent people, bandying around some absolutely crackpot notions. [sigh]

    5. Jeff@Ashe

      Re: Neat

      IIRC the Pound–Rebka experiment (1959) used the Mossbauer effect to test gravitational time diation.

  2. A.P. Veening Silver badge

    Complications

    If the accuracy of atomic clocks is dependent upon gravity (as just demonstrated), we may have a serious problem with the definition of time as that is currently defined using atomic clocks. And the rest of the SI is also rather relative because of this (the unit of length is derived from the unit of time by light speed).

    1. Saruman the White

      Re: Complications

      The effects of gravity on time has been known for nearly a century. Surprisingly the SI definition actually takes that into account; a measurement of (say) a second will be identical whether made on the surface of the Earth or in deep space; however an absolute comparison of the measurements will show a (very small) difference due to gravity-induced time dilation.

      In order to detect gravity waves, they will need a network of four or more clocks equally distant from each other. One would then measure the absolute differences in the clock readings caused by gravity waves; by looking at the order in which the clocks drift back and forwards it becomes possible to determine the direction from which the gravity wave hit us.

    2. TitterYeNot

      Re: Complications

      we may have a serious problem with the definition of time as that is currently defined using atomic clocks. And the rest of the SI is also rather relative because of this (the unit of length is derived from the unit of time by light speed).

      Time is relative, we know this.

      A second for you, whether measured using your trusty pocketwatch or the electron oscillation frequency in the fancy atomic clock taking up most of your office, is always a second, as c is constant (and so your metre is always exactly a metre etc.)

      A second for another observer in a different gravitational potential or going at very different velocity through space will be different to your second though, and its by comparing the two that we can detect the distortions in space time that Einstein stated would be caused by gravity. However, for them, c is also constant, so their second will always be exactly one second and a metre exactly one metre to them.

    3. Brewster's Angle Grinder Silver badge

      Re: Complications

      "If the accuracy of atomic clocks is dependent upon gravity (as just demonstrated), we may have a serious problem with the definition of time as that is currently defined using atomic clocks."

      There wouldn't be a problem with the definition of time. But we would (and do) have to be careful comparing different clocks.

      This actually caused a problem early on and the time signal formed from atomic clocks (TAI) ended up being a smeared average of clocks at different altitudes. I don't know why this mistake was made, since it was well understood that time on the earth's surface would be different to time at it's centre or at the centre of the solar system, and we had (and still have) different timescales to deal with this.

      1. Yet Another Anonymous coward Silver badge

        Re: Complications

        >There wouldn't be a problem with the definition of time.

        Except the second is defined for clocks sitting at the Earth's surface

        Which is defined as g=9.81m/s^2

        Which depends on the definition of a second

        1. ibmalone Silver badge

          Re: Complications

          Except the second is defined for clocks sitting at the Earth's surface

          Which is defined as g=9.81m/s^2

          Which depends on the definition of a second

          No,

          "The second is the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom."

          https://physics.nist.gov/cuu/Units/current.html

          Nothing else is needed for the units system to be consistent, it'll work anywhere.

          Now if you want to measure calendar time you need a frame of reference. I can't find in a quick search where ISO time incorporates this, but that's the point at which g matters.

          1. Yet Another Anonymous coward Silver badge

            Re: Complications

            g (ie GM) is involved because the standard clocks are corrected for General Relativity to mean sea level. It being slightly impractical to run all the atomic clocks in completely flat spacetime. Can't remember if the second was defined at msw or the clocks are simply corrected to msw before being compared.

            Standard atomic clocks are so accurate that you use them to define the geoid height at the lab, which you then use to correct each clock when they are compared - it is a slight chicken-egg problem.

        2. mosw

          Re: Complications

          >Except the second is defined for clocks sitting at the Earth's surface

          >Which is defined as g=9.81m/s^2

          >Which depends on the definition of a second

          As I understand it, gravity distorts both space and time, but the relationship between time, length and the speed-of-light remains constant. So a metre measured with the standard at sea level will be the same as a metre measured out in space using local clock references.

  3. ColonelDare
    Thumb Up

    But how long must we wait?

    > "....could further be used to explore geophysical phenomena, detect gravitational waves, test general relativity, and search for dark matter."

    (Estimates may be rounded to 18 decimal places)

    1. Yet Another Anonymous coward Silver badge

      Re: But how long must we wait?

      Think how much Ti is going to charge for the graphing calculator to do that

  4. Michael H.F. Wilkinson Silver badge
    Thumb Up

    Cool!

    Literally and figuratively

  5. Zog_but_not_the_first Silver badge
    Trollface

    Do they...

    Adjust them for daylight saving twice a year?

    Just asking.

    1. John Robson Silver badge

      Re: Do they...

      "Adjust them for daylight saving twice a year?

      "Just asking.

      No - they do however adjust our clocks a up to twice a year, by a second, to account for the inconsistent, and imprecise, rotation of the earth...

  6. Anonymous Coward
    Anonymous Coward

    Pseudoscience

    Gravitation waves and dark matter would affect all clocks on Earth (gravity can not be shielded), so there would be no way to detect them, let alone prove any change in time was due to these phenomena.

    1. Saruman the White

      Re: Pseudoscience

      However gravity waves are not constant; each one moves in a particular direction, so the clocks on one side of the Earth would be affected before those on the other side.

      Same principal as LIGO, but orders of magnitude more sensitive.

    2. tfb Silver badge
      Boffin

      Re: Pseudoscience

      Um: The LIGO / VIRGO scientists may have something to say about that.

    3. Glen 1 Silver badge

      Re: Pseudoscience

      Yeah, just like climate change </sarcasm>

  7. Anonymous Coward
    Anonymous Coward

    Huh?

    "Grav waves and dark matter have an effect on gravity..."

    Dark matter has an effect on gravity, gravitational waves are a change or variation in/of gravity. Saying that gravity waves have an effect on gravity is like saying a change in something creates that change.

    "...and thus time, variations of which..."

    There are not different varieties of time. Variations can occur in time, but it's all the same sort of time.

    "As you'd expect, if two of these clocks were placed at different altitudes near the Earth's surface, the higher one would tick slightly faster than the lower one, due to classic time dilatation."

    There're two types of time dilation: gravitational, where the local rate of time is affected by mass, and relativistic, where the local rate of time is affected by spatial motion; there is no "classic" variety.

    "...an effect sometimes called the gravitational redshift."

    Only people who don't know what they're talking about would call gravitational time dilation "gravitational redshift": time dilation and 'red-shift' are two entirely different phenomena.

    And no, I don't think I'm just being pedantic - these mistakes, far from informing people, just mislead them.

    1. Chemist

      Re: Huh?

      "Dark matter has an effect on gravity, gravitational waves are a change or variation in/of gravity."

      AFAIK gravitational waves distort spacetime and change lengths & time as they pass. They are not in themselves 'gravity'

      A lot going on here so I've not been able to refresh my memory on this.

    2. steelpillow Silver badge
      Boffin

      Re: Huh?

      It's more subtle than that. Mass and energy tell spacetime how to curve, the curvature of spacetime tells matter and energy how to move. Gravity is effectively the local curvature of spacetime induced by the presence of mass and energy, so as mass moves around the curvature follows it and as the curvature changes so the mass follows it in a tight feedback loop. Depending where you are looking on the loop, effects on/by are interchangeable.

      On time dilation, redshift is just how time dilation is measured, regardless of whether it originated in motion or gravity. A "gravitational redshift" is a measure of gravitational time dilation and is a perfectly sensible way to express that.

      Oh, and gravitational waves are indeed "gravity", just as light waves are "light".

  8. Terry 6 Silver badge
    Joke

    So..

    This new clock is not going to be on my Xmas prezzie list then? :-(

  9. Will Godfrey Silver badge
    Linux

    Enquiring minds would like to know?

    How can they be certain it's time that's changing, and not the mechanism for measuring it?

    1. Christoph Silver badge

      Re: Enquiring minds would like to know?

      By comparing multiple mechanisms in different places

  10. Christoph Silver badge

    Accuracy of 10 to -18 is much better than one second in the age of the Universe!

  11. Schultz
    Boffin

    Nice, but ...

    I don't know why they threw in that statement about detecting gravitational waves.

    The waves observed by LIGO have periods in the millisecond range (see: https://www.ligo.org/detections.php), but the averaging time of this experiment to get to the ultimate <1e-18 uncertainty seems to be hours to days (see: https://www.nature.com/articles/s41586-018-0738-2/figures/3). I didn't do a deep dive, but I think their measurement is many orders of magnitude too slow to see gravitational waves.

    1. Rich 11 Silver badge

      Re: Nice, but ...

      I didn't do a deep dive, but I think their measurement is many orders of magnitude too slow to see gravitational waves.

      You'd better send them a postcard and let them know, then.

    2. John Mangan

      Re: Nice, but ...

      LIGO only measures certain frequencies corresponding to certain cosmological phenomena. There are other phenomena 'expected' to produce gravitational waves in different frequency ranges.

      LISA for instance will be looking in a lower frequency range.

    3. Anonymous Coward
      Anonymous Coward

      Re: Nice, but ...

      It doesn't matter what work is done by however many people that have dedicated whatever significant portion of their professional lives to a specific topic but there will ALWAYS be at least one commentard who notices the glaringly obvious mistake/ommision that they have made based on approximately 3 minutes of reading and cogitation.

      Think of the money we could save if we got these people involved at the start of projects!

      You know, it is also these kind of comments that contribute to my woefully low view of the opinion of 'the man in the street' on ANY topic.

      1. Thoguht Silver badge

        Re: Nice, but ...

        I've only spent 3 minutes reading your post and cogitating about it, but I have noticed a glaringly obvious mistake in your "ommision".

        1. John Mangan

          Re: Nice, but ...

          @Thoguht

          Bugger! That is all.

    4. tfb Silver badge
      Boffin

      Re: Nice, but ...

      Sources of gravitational waves have varying characteristics & the resulting waves have different frequencies. Conveniently one significant source -- the inspirals of massive, very compact objects (black holes & neutron stars) happens, really, at audio frequencies, and LIGO / VIRGO has been designed to be sensitive in that spectrum (you can listen to the chirps it detects which is just an astonishing thing I think).

      But there are other sources of gravitational waves, many of which have much lower frequencies (I'm not sure if any significant sources have higher frequencies than what LIGO / VIRGO hears but I suspect not on the grounds that you'd need more mass in a smaller space to do that, and you end up inside an event horizon in that case...). An example of such sources are binary supermassive black holes in orbit around each other. These may have orbital periods of months to years, and the resulting gravitational radiation has periods of months or years therefore, and frequencies measured in millionths or billionths of a Hz. LIGO simply isn't sensitive in this range. But arrays of very accurate clocks, suitably far apart, can be and this is what these people are interested in.

      Astonishingly, we already are using such arrays of accurate clocks to look for gravitational waves! It turns out that some pulsars -- 'millisecond pulsars', which have rotational periods in the 1-10ms range -- are spectacularly accurate clocks: until fairly recently (and, perhaps, still) they were more accurate than the best atomic clocks. So, if you can find a suitable collection of millisecond pulsars and listen to them for a long period of time, you may see variations in their apparent rate as low-frequency gravitational waves pass. And people are doing this: see the Wikipedia page on Pulsar timing arrays.

      What this goes to show is that, however cool an idea you come across, astronomers are already doing something cooler.

  12. J4

    Shoutout to Ms Quach

    Fascinating concept and yet again a welcome relief from the tedious daily political screeching that fills the airwaves to no purpose, crowding out stories of genuine human achievement.

    And separately a thank you to Ms Quach for consistently writing up complex topics in an interesting and digestible way.

  13. Antonius_Prime
    Coat

    What truly enquiring minds would like to know...

    Is when are Apple going to try to stick one in a watch to overcharge people for?

    (Mine's the one with the ancient iPhone in the pocket, ta!)

  14. Daedalus Silver badge

    QM is hard!

    electrons oscillated by jumping between energy levels

    Not exactly. Electrons are not thought of as oscillating in any sense when they are bound to atoms. Indeed, it was the very idea that they were oscillating that caused so much trouble back in the 1900's, since by Maxwell's equations they should radiate constantly while "orbiting" the nucleus.

    Atoms emit photons when the electrons around the nucleus change state. This is expressed as the entire ensemble changing state, not just one electron.

    Ytterbium and other "rare earths" have a special property: some of their transitions are extremely precise because the electron states are unaffected by the environment, which tends to smear out the energy levels of other elements. This is used commonly in glassblowers goggles, that are able to filter out just the yellow glow of hot sodium and nothing else, making it easier to see the work.

    It's the narrow spectral line, and the cold temperature, that enables the ytterbium to be used as a clock here.

    1. ibmalone Silver badge

      Re: QM is hard!

      "electrons oscillated by jumping between energy levels

      Not exactly. Electrons are not thought of as oscillating in any sense when they are bound to atoms. Indeed, it was the very idea that they were oscillating that caused so much trouble back in the 1900's, since by Maxwell's equations they should radiate constantly while "orbiting" the nucleus."

      They kind of are when they transition between levels in, say, a laser; absorb photon, go up a state, release photon, go down one, oscillation between levels. Though in context it's wrong, since it suggests that's the oscillation rate between states being measured, while presumably it's actually the photon frequency.

      Getting your mind around what the Bloch equations mean for individual atoms is tricky, I eventually settled on photons acting like spanners cranking the state. Which is almost certainly terribly misleading, but does allow visualising them being wielded by tiny quantum mechanics.

  15. danR2

    Neither in the article, nor in the comments, is it clear to me that the time-resolution of these clocks is sufficient to track relative variations in the rate of time between spatially displaced clocks. This would speak to the sort of periods involved in measuring gravitational waves. Alternatively, one could sample the readouts at varying rates and signal-average the readout instances, and look for spikes in the sample-rate spectrum.

    Ie, one could sample the readouts 1000 times at 0.1 ms, at 0.2, 0.4.... 6.4ms ... etc.

    If I'm not clear, I need my morning second cuppa, sorry. Maybe someone can repair the above so it makes more sense.

    1. willi0000000

      @danR2

      i found that the NIST site (as usual) to be helpful.

      try: https://www.nist.gov/news-events/news/2018/11/nist-atomic-clocks-now-keep-time-well-enough-improve-models-earth

  16. Cynic_999 Silver badge

    So how do you compare them?

    So you have two different clocks separated by a large distance. I can see how you can measure a constant difference in time-keeping as the error would get bigger & bigger. But if a gravity wave goes past and one clock *momentarily* speeds up or slows down relative to the other, how do you compare the instantaneous time readings of 2 clocks separated by a large distance? The data from the clock to the distant observer cannot travel faster than the speed of light (which is not a constant in different mediums, and possibly is affected by gravity itself).

    1. tfb Silver badge

      Re: So how do you compare them?

      Well, take the example where we already do this: the 'clocks' (pulsars) conveniently emit a sequence of flashes, one per 'tick'. And you sit and watch the rate these flashes arrive at for a number of the clocks. Changes in the relative rate tell you what you need to know.

      (And, apparently, yes, there is a problem in that the timing can be off due to uncontrolled effects when the pulses are passing through the atmosphere, since we're measuring these things on Earth currently. They use as many pulsars as possible to average this out I think.

  17. mpc755

    Displaced supersolid dark matter is curved spacetime

    Dark matter is a supersolid that fills 'empty' space, strongly interacts with ordinary matter and is displaced by ordinary matter. What is referred to geometrically as curved spacetime physically exists in nature as the state of displacement of the supersolid dark matter. The state of displacement of the supersolid dark matter is gravity.

    The supersolid dark matter displaced by a galaxy pushes back, causing the stars in the outer arms of the galaxy to orbit the galactic center at the rate in which they do.

    Displaced supersolid dark matter is curved spacetime.

  18. StargateSg7 Bronze badge

    AND.....in case anyone is wondering what USE this type of technology has for the real world, I can tell that IF these time pieces were put in for GPS (Global Positioning Sytem aka Galileo, GLONASS, Beidou, etc), then our positioning accuracy would go from the current unaugmented 30 metres (96 feet) or 10 metres augmented (30 feet) downto SUB-MILLIMETRE-scale accuracy. That make GPS-based self-driving automobiles, lorries (Semi-Trucks), planes, ships, delivery drones a lot more viable!

    ...AND...

    The data bandwidth of mobile phones could be increased a hundred-fold by using a super-precise TIME-AND-PHASE-based QAM (Quadrature Amplitude Modulation) so that instead of the current maximum of 64 to 4096 symbols represented per signal-set within the QAM-64 to QAM-4096 communications digital modulation schema, we could have QAM-192K or even QAM-ONE-MEG because we can MORE PRECISELY delineate where a QAM-symbol boundary starts and stops within the QAM digital modulation scheme.

    See background:

    https://en.wikipedia.org/wiki/Quadrature_amplitude_modulation

    If we were able to move even to a 128K QAM, actual mobile phone data downloads AND uploads would be TRULY symmetrical at about 682 Megabits per second with ECC (Error Correction) and with One-Mega-QAM, we could get 5.4 Gigabits per second upload AND download Full Duplex PER USER!

    Sooooooo......from a COMMERCIAL point-of-view, PRECISE clocks make a BIG DIFFERENCE in GPS accuracy AND wireless data bandwidth !!!!!

    1. Spherical Cow Bronze badge

      THANK you FOR sharing THAT fun POST with US.

    2. Kevin McMurtrie Silver badge

      AND...

      Hold on...

      GPS is messed up by atmospheric distortion and no clock can fix that. You need a signal from a nearby reference point to compensate for it.

      What you're talking about with QAM sounds like not needing to waste bandwidth on a self-aligning transmission pattern for phase. (I'm bad at RF...Trellis encoding?) No phase drift would be a small improvement in a lab. In the real world you're back to atmospheric and multi-path distortions making a huge mess plus the usual random noise making your signal miss its points. I don't see any gains at all.

      A more interesting use might be checking the drift between a super-accurate Earth clock and astronomical timekeepers.

      1. StargateSg7 Bronze badge

        Re: AND...

        You actually hinted at HOW the actual gain over current atmospheric and multi-path distortions will occur, because by adding in EXTRA signal "ECC frames/packets" that are used as REFERENCES, they could be compared to an saved-internal-to-phone IDEAL ECC frame/packst signal and those HIGHLY accurate time and phase difference between the IDEAL reference signal and the one stored in the phone could tell you how much general distortion and multi-path is taking place within your current signal environment.

        That ALLOWS you to figure out how much the QAM "place-points" are distorted from what should be ideal locations. You're STILL going to get an ENORMOUS bandwidth increase because the distortions are compensated for. An RF researcher in the 1970's from Simon Fraser University in Canada PIONEERED the use of PRE-DISTORTION to figure out how irregular signals were actually distorted from an ideal signal and how such signals could be compensated-for at the reception side.

        https://www.edn.com/design/analog/4369663/RF-predistortion-straightens-out-your-signals

        ALL modern mobile devices use his pioneering 1970's era research AND with a better, more accurate clock your digital signal pre-distortion and UNdistortion system is able to more effectively figure out HOW to compensate for time and phase distortions allowing QAM symbols to be spaced closer together and allowing MORE symbols within the QAM schema which give you much greater bandwidth.

        AND YES I ran it through with one of our RF engineers and he sat me down to tell me this is "Old News" and that QAM symbology recognition techniques in current development WILL allow for OVER one million symbols per RF digital modulation set with higher resolution clocks. And it seems MUCH RESEARCH has ALREADY been done in this area on using more accurate clocks, which is WHY Wifi 802.99x and 6G will be on the order of TERABITS per second bandwidths!

        1. tfb Silver badge
          Alien

          Re: AND...

          I don't know if it's sad or not, but I'm just not reading this comment & the previous one because of the 'crank capitalisation'.

          1. Anonymous Coward
            Anonymous Coward

            Re: AND...

            @tfb I'm prepared to offer 'a little sad but understandable'?

            1. Glen 1 Silver badge

              Re: AND...

              Ah BOB Stargate, why do you even have separate accounts if you're going to be so easily recognised?

              1. StargateSg7 Bronze badge

                Re: AND...

                ".....Ah BOB Stargate, why do you even have separate accounts if you're going to be so easily recognised? ...."

                ---

                Because I am NOT Bombastic Bob! I am StargateSG7, a user based in Vancouver, Canada. Bombastic Bob, I think is based in Southeast England. We for SOME REASON have the same writing style using that OPPOSING caps style. I also think we probably came from the same pressure-cooker background of 1980'era MiniComputer/Mainframe computing and Large Data Systems management which probably EXPLAINS WHY we are so hyperactive and well.....BOMBASTIC....!!!!

                I do machine vision systems and video processing research for various entities of which I have a stake in. Bombastic Bob I believe is a SysOps/DevOps person.

                I AM NOT BOMBASTIC BOB !!!! Ya Got The Wrong Guy!

                ---

                Now back to the main subject at hand!

                QAM bandwidth is governed by the number of symbols which are in fact a series of radio waves of a specific amplitude and phase that are SUPPOSED to appear in a Specific Quadrant when those signals are displayed on a Vectorscope (which is a type of Oscilloscope -- i.e. do note the word Quadrature!).

                When you divide up a vectorscope into quadrants and place TARGET-points within those qradrants, ANY incoming signal of a specific frequency that has it's amplitude HITTING those target points is considered a signal that signifies the digital signal symbol that represents that target point (i.e. example the binary digit 15 or 1111 in bitwise notation for any RF signal that say....hits the quadrature target at XY-Point X:200, Y:-200 +/- 0.2% of graph size)

                Signals that DO NOT hit those target points on the scope are rejected as NOT being part of any symbol set.

                Now the problem is that RF signals have multipathing and reflect, diffract, refract and otherwise mis-time themselves. If only one or two waveforms do that, then we can easily have circuitry that REJECTS those signals as NOT being part of a QAM modulation schema.

                BUT if MORE THAN ONE set of waveforms has the same general amount of multipath and distortion behaviour, then the circuits MUST ASSUME that it is the SIGNAL ENVIRONMENT itself that is causing the problems and thus attempt to recover those distorted signals by creating a PLUS/MINUS DIFFERENCE-based error correction scheme that ACCOUNTS for those distortions.

                So the circuits look for IDEAL SIGNAL ECC/Correction-specific RF Frames or Packets every few seconds or even microseconds that are of a format that are considered IDEAL signals. When the RECEIVED IDEAL signals are compared against the internal-to-phone's or wireless router's IDEAL SIGNAL reference waveform, then we can figure out how much time and phase distortion is occurring and then apply THAT distortion difference calculation to ALL OTHER incoming signals so we can determine if the incoming digital RF signals hit the QAM signal quadrature placement points which indicates they are a VALID QAM symbol!

                Today, it's usually QAM-64 (16 points per quadrature) or QAM-256 (64 points per quadrature) that represents up to 64 symbols or 256 symbols per modulation set. NOW as of 2018 QAM-1024 and QAM-4096 are coming out within specialty systems (usually video and mobile voice phone oriented) because a few "dropped" symbols doesn't mean all that much to understanding a voice of video stream. You would hear static or see macro-blocks. That is NOT too big of a deal for the average user/consumer!

                BUT with DIGITAL DATA where every bit counts, we still use OLDER QAM because we can more reliably recover digital data from an RF signal. However, the data rate is much LOWER!

                Soooooo, with much more precise clocks, we can BETTER place the QAM symbols with the QAM quadratures so they can be recovered more effectively within even a heavily distorted, time-delayed and out-of-phase RF signals environment.

                The MORE IDEAL reference signals are sent closer together, the more accurately I can MEASURE time and phase distortions to BETTER recover actual digital data! Ergo, i get MUCH HIGHER bandwidth into the Terabits-per-Second range!

                And with QAM-128-Kilo or QAM-ONE-Mega we can have 128 Thousand or One Million symbols per RF digital modulation signal set which means ENORMOUS full-duplex download AND upload bandwidth per user!

                which equals Tottenham Football Match Watch-on-the-London-Tube Heaven! (or here in Canada, it means I can watch the Vancouver Canucks hockey team PROBABLY actually make it to the playoffs AND maybe even WIN the Stanley Cup in the 2019 playoffs all the WHILE watching from my tablet whilst seated lazily on my boat anchored in English Bay listening to the Seagulls float by and having two pints at a time!)

                Is THAT not a good enough reason to get QAM-ONE-Mega up and running sooner rather than later?

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