I just don't see this becoming viable by 2026 to just toss ICE vehicles completely, just too many things we haven't figured out yet.
A lot of these problems actually have solutions, but that's incidental. VW Is saying they will start selling their final ICE ranges from 2026. They don't plan to produce a new "platform" after that, so they ar ebetting that ICE cars become niche by 2040 or so.
What about the researchers at the National Institute for Metrology Research, Italy, and the Australian Nuclear Science and Technology Organisation who are working on the silicon-28 sphere to redefine the kilogram in terms of the Planck constant by determining Avogadro’s constant?
With a laser functioning as "optical tweezers" one can isolate single subatomic particles (electron, proton, well-characterized ions ref: https://journals.aps.org/rmp/a... ) set the standard kilogram to the appropriate number of one of those and bid all your metal alloys under bell-jars bye-bye. That is, define the kilogram to be something like 1e30 electron masses or 6e26 proton masses. whichever is more convenient.
This approach was considered -- there were a lot of attempts to make a reasonably large lump of silicon pure enough and with a perfect enough crystal lattice that the number of atoms in it could be counted to sufficient accuracy, whereupon the mass of one atom of (a specific isotope of) silicon would become the reference. The Kibble balance (which ties the kilogram to Planck's constant and so to the energy of photons of specific wavelengths) got to the required accuracy (required so that the mass of the kilogram didn't change too much when the standard changed) first.
These machines will provide the standard for weighing objects -- and that means no more dusting of [sic] old lumps of alloy to ensure they stay pure and accurate. Providing that "these machines" are constructed and calibrated accurately, and the devices they use in performing their function (ampere, gram-force, et.al.) are themselves positively known. Especially in a world where you can't even depend upon the gravitic 'G' to be constant anywhere on the surface.
That's not how it works. In the new regime, the kilogram will be calculated from the second, defined in terms of the frequency of radiation produced by a particular atomic transition, using fixed values of the speed of light and Planck's constant. It doesn't depend on any kind of machine.
The machine is needed to work out the definition in these terms sufficiently accurately that the actual mass of the kilogram will not change enough to cause any problems when we shift to the new standard. Once the shift is done, the machine is no longer needed (except as one available type of very accurate mass measuring device).
I'm sure this is a valid approach, but I think they will want more detail. What plants? What kind of structure will you grow them in? Will they need soil, if so, how much? Can they grow in pure CO2 (and at what range of pressures)? If not, what other gases will they need? What additional nutrients will they need? Will you be able to recycle those nutrients from what's left of the plants after you extract the glucose? etc.?
Of course we don't have the luxury of taking 1000 Earths with slightly different conditions and measuring their climates over centuries. But there are established approaches that apply in this situation. As one very oversimplified idea among many, you can exclude part of the data you do have, use the rest to initialise your model and see how accurately it reproduces the missing data. You can repeat this by excluding a different part of the data and running the same process. Your hypothesis is that your model tracks reality within quantified limits. This can be disproved.
There are many other problems with the paper. They're claiming it's done using silver and gold, for instance, neither of which have shown any evidence of superconducting at all. It's possible that if you mix them up in the right combination they somehow start superconducting, but it's a really extraordinary claim to add to the room temperature (okay, -35F) superconducting claim.
Silver and gold are such good conductors because it's hard for moving electrons to excite lattice vibrations. That exact reason makes them a poor candidate for a type 1 superconductor, where lattice vibrations link the electrons in pairs which are then bosons and can flow much more freely.
The paper claims that their material consists of nanometer sized particles of silver embedded in gold. This is so small that the usual atomic lattices essentially don't exist -- most atoms are at, or very close to, a silver-gold boundary, so the behaviour of bulk silver and bulk gold are not really relevant.
It does have solar panels, but they are not very big because the sunlight on it will be very bright. In fact it has two sets -- bigger ones for use further from the sun, which can be folded away, and smaller ones with extra cooling pipes which can be used closer to the Sun where the light is brighter. Even they will just need to "peep" out from behind the heat shield at the closest approaches.
The article makes no mention of remote updates, let alone wireless ones. A physical port inside the device (perhaps behind a locked panel) makes sense for most devlces. If the device is already remotely accessible in any way (eg to allow a physician to plug into it and recover health data) then it potentially needs security updates. If not, then being able to apply a (suitably checked and signed) firmware update with a special cable may avoid the need for surgery and/or an expensive replacement device. Assuming they get the details right, this sounds sensible.
If that old thing can see something so unique and far away
I still don't understand how they can determine distances of such far-out objects. Yes I am aware of standard candles, and that we "know" how far away they are based on observed brightness. But observed brightness isn't just impacted by distance, it is also impacted by the size of the object. So how can we be so sure that these standard candles are not bigger or smaller than we assume they are?
Are the distances simply so large, that a standard candle would need to be exponentially larger/smaller than our assumed size in order to significantly impact the calculated distance?
Standard candles are things that have a fixed total brightness (or at least a brightness that we can work out independent of their size).
For instance a certain type of supernova is believed to happen when a white dwarf star, slowly accreting matter from a companion, finally gets too massive to support itself and collapses into a neutron star. Regardless of the mass of the original white dwarf, this mass at which this collapse happens is pretty much the same, and so the total brightness of this type of supernova is more or less constant.
Dark matter has always struck me as a kludge. It amounts to "we don't know WTF is going on, so here's our fudge factor". There is no evidence that dark matter exists, other than the fact that gravity on large scales doesn't behave the way cosmologists expect. Two other possibilities receive too little attention:
- Our current theory of gravity does not apply on the scales we are observing, i.e., the theory is incomplete.
- Physical laws are not constant. e are looking at very distant objects, and seeing them in the distant past. Perhaps universal constants are not, in fact, constant across large spans of space and/or time.
So now they've discovered a galaxy where the kludge factor of dark matter is not needed. Maybe this will prompt more cosmologist to consider the alternatives...
Actually this evidence supports Dark Matter and contradicts those two theories quite nicely. They both describe universal phenomena -- if the laws of gravity are different, or physical laws are changing the every distant galaxy should show the same anomalous motion. On the other hand if the usual anomalous motion is due to "stuff" (dark matter) then it's not very surprising that some rare event (like a collision) could have separated this galaxy from its original dark matter.
Rotational speeds have been explained rather nicely by other theories, but dark matter/energy has become astronomical doctrine so those better-fitting yet alternate theories get scoffed at.
Can you give a RECENT example of another theory that explains rotational speeds and doesn't contradict any other observations?
Does it also explain ANY of the other things that Dark Matter explains?
You're confused. Dark matter and dark energy aren't concrete things. They're placeholders for the remainders that don't fit the currently understood data. They are the X and the Y in an equation we haven't yet solved. X and Y are in fact the "only" solutions to the equation, because that's a tautology. The solution to the equation is the solution to the equation. But because we don't know what they are they could turn out to be almost anything, or a combination of things. There are a lot of theories as to what they might be, but none of them is definite, and none will be until we gather more data.
But you can say that for anything outside your own head. Everything in the entire universe is just a placeholder to fit a set of observations. At some point we decide the the observations are detailed and consistent enough that we'll stop worrying about this and talk as if the object really exists. If you look at recent data, dark matter has reached that point. Multiple approaches give a pretty consistent idea of where it is, how much of it there is, and some aspects of how it behaves. Dark energy not so much, yet.
Two problems: (1) we can measure the rotational velocities (2) The galaxies are old enough to have rotated 50 or so times and the spiral structure is still there.
What makes it even more kludgy is that this dark matter is supposed to make up a significant percentage of the universe. Except there is *NONE* in our solar system or it's immediate vicinity. If there was any dark matter locally then General Relativity would not explain the planets orbits around the Sun with such precision because it's does so using only visible matter.
This is a huge problem for dark matter because it presumes that our solar system is somehow very special, which is frankly too fantastical.
This is just wrong. This paper: https://arxiv.org/pdf/1404.193... (which also has a lot of interesting background) collects estimates of the density of dark matter in this part of the galaxy, most of which are around 0.01 solar masses/ cubic parsec (around 10^-21 kilograms/m^3). So even if the solar system was pervaded by dark matter of this density it would make no measurable difference to anything. For example the entire sphere up to Earth's distance from the Sun would contain about a billion tons of dark matter, the same as the mass of a extra 1 km diameter asteroid.
There will still be a role for a power grid to redistribute power over space and time to match supply and demand even if a significant amount is produced, stored and consumed locally. It will need a much more sophisticated pricing, quality of service and regulatory model, but it will still be very much essential infrastructure.
DIfferent observers would calculate different lengths of time (and distances in space) between the sun going dark and the last light from the Sun passing the Earth. In relativity, none of these observers is "special". All their calculations are equally correct. What they would agree on is the speed that that the light from the Sun was travelling at. So some might see the light taking 1 second to travel 300 000 km from the Sun to the Earth, others would see it taking about 8 minutes to travel 150 000 000 km (no one would see anything longer than that).
You could take a look at what Software Carpentry https://software-carpentry.org... teach. They cover relatively practical skills like version control, regression tests, etc. which are still a big step forward for many research programmers.
At a more conceptual level you are aiming towards "abstraction" and "separation of concerns". Self-taught academic programmers are usually quite good at getting individual methods to work, but hopeless designing software so that changes are localised.
This is about the details of how the explosion happens. A star is a pretty big thing and it does not all explode at once. The explosion starts pretty far in and has to somehow get through or past the outer layers of the star before we can see it. The details of how that happens are very unclear.
You can combine multiple mirrors within a single telescope, but you have to keep them aligned to enormous accuracy (50nm or so) so you still need a massive framework.
You can combine multiple telescopes by actually steering the incoming light to a meeting point and interfering it, but it's incredibly hard to do. Everything needs to be super stable.
You can't get (much) more detail by combining multiple digital images. You can get a bigger image, or a "deeper" image (one that shows fainter objects) but not a more detailed one.
Slashdot Mirror
Isn't this in combination with the GDPR just going to make it plain illegal for European data controllers to put their data on US owned servers?
I heard it was making a second pass by Saturn next year
Definitely not. It's nowhere near Saturn and doesn't even begin to have the fuel to get there.
I just don't see this becoming viable by 2026 to just toss ICE vehicles completely, just too many things we haven't figured out yet.
A lot of these problems actually have solutions, but that's incidental. VW Is saying they will start selling their final ICE ranges from 2026. They don't plan to produce a new "platform" after that, so they ar ebetting that ICE cars become niche by 2040 or so.
What about the researchers at the National Institute for Metrology Research, Italy, and the Australian Nuclear Science and Technology Organisation who are working on the silicon-28 sphere to redefine the kilogram in terms of the Planck constant by determining Avogadro’s constant?
The Kibble balance folks got there first.
With a laser functioning as "optical tweezers" one can isolate single subatomic particles (electron, proton, well-characterized ions ref: https://journals.aps.org/rmp/a... ) set the standard kilogram to the appropriate number of one of those and bid all your metal alloys under bell-jars bye-bye. That is, define the kilogram to be something like 1e30 electron masses or 6e26 proton masses. whichever is more convenient.
This approach was considered -- there were a lot of attempts to make a reasonably large lump of silicon pure enough and with a perfect enough crystal lattice that the number of atoms in it could be counted to sufficient accuracy, whereupon the mass of one atom of (a specific isotope of) silicon would become the reference. The Kibble balance (which ties the kilogram to Planck's constant and so to the energy of photons of specific wavelengths) got to the required accuracy (required so that the mass of the kilogram didn't change too much when the standard changed) first.
These machines will provide the standard for weighing objects -- and that means no more dusting of [sic] old lumps of alloy to ensure they stay pure and accurate.
Providing that "these machines" are constructed and calibrated accurately, and the devices they use in performing their function (ampere, gram-force, et.al.) are themselves positively known. Especially in a world where you can't even depend upon the gravitic 'G' to be constant anywhere on the surface.
That's not how it works. In the new regime, the kilogram will be calculated from the second, defined in terms of the frequency of radiation produced by a particular atomic transition, using fixed values of the speed of light and Planck's constant. It doesn't depend on any kind of machine.
The machine is needed to work out the definition in these terms sufficiently accurately that the actual mass of the kilogram will not change enough to cause any problems when we shift to the new standard. Once the shift is done, the machine is no longer needed (except as one available type of very accurate mass measuring device).
Incidentally G is constant everywhere. g varies
They were, they failed.
https://www.nasa.gov/feature/j...
I'm sure this is a valid approach, but I think they will want more detail. What plants? What kind of structure will you grow them in? Will they need soil, if so, how much? Can they grow in pure CO2 (and at what range of pressures)? If not, what other gases will they need? What additional nutrients will they need? Will you be able to recycle those nutrients from what's left of the plants after you extract the glucose? etc.?
Evidence please?
Of course we don't have the luxury of taking 1000 Earths with slightly different conditions and measuring their climates over centuries. But there are established approaches that apply in this situation. As one very oversimplified idea among many, you can exclude part of the data you do have, use the rest to initialise your model and see how accurately it reproduces the missing data. You can repeat this by excluding a different part of the data and running the same process. Your hypothesis is that your model tracks reality within quantified limits. This can be disproved.
There are many other problems with the paper. They're claiming it's done using silver and gold, for instance, neither of which have shown any evidence of superconducting at all. It's possible that if you mix them up in the right combination they somehow start superconducting, but it's a really extraordinary claim to add to the room temperature (okay, -35F) superconducting claim.
Silver and gold are such good conductors because it's hard for moving electrons to excite lattice vibrations. That exact reason makes them a poor candidate for a type 1 superconductor, where lattice vibrations link the electrons in pairs which are then bosons and can flow much more freely.
The paper claims that their material consists of nanometer sized particles of silver embedded in gold. This is so small that the usual atomic lattices essentially don't exist -- most atoms are at, or very close to, a silver-gold boundary, so the behaviour of bulk silver and bulk gold are not really relevant.
It does have solar panels, but they are not very big because the sunlight on it will be very bright. In fact it has two sets -- bigger ones for use further from the sun, which can be folded away, and smaller ones with extra cooling pipes which can be used closer to the Sun where the light is brighter. Even they will just need to "peep" out from behind the heat shield at the closest approaches.
The article makes no mention of remote updates, let alone wireless ones. A physical port inside the device (perhaps behind a locked panel) makes sense for most devlces. If the device is already remotely accessible in any way (eg to allow a physician to plug into it and recover health data) then it potentially needs security updates. If not, then being able to apply a (suitably checked and signed) firmware update with a special cable may avoid the need for surgery and/or an expensive replacement device. Assuming they get the details right, this sounds sensible.
If that old thing can see something so unique and far away
I still don't understand how they can determine distances of such far-out objects. Yes I am aware of standard candles, and that we "know" how far away they are based on observed brightness. But observed brightness isn't just impacted by distance, it is also impacted by the size of the object. So how can we be so sure that these standard candles are not bigger or smaller than we assume they are?
Are the distances simply so large, that a standard candle would need to be exponentially larger/smaller than our assumed size in order to significantly impact the calculated distance?
Standard candles are things that have a fixed total brightness (or at least a brightness that we can work out independent of their size).
For instance a certain type of supernova is believed to happen when a white dwarf star, slowly accreting matter from a companion, finally gets too massive to support itself and collapses into a neutron star. Regardless of the mass of the original white dwarf, this mass at which this collapse happens is pretty much the same, and so the total brightness of this type of supernova is more or less constant.
Dark matter has always struck me as a kludge. It amounts to "we don't know WTF is going on, so here's our fudge factor". There is no evidence that dark matter exists, other than the fact that gravity on large scales doesn't behave the way cosmologists expect. Two other possibilities receive too little attention:
- Our current theory of gravity does not apply on the scales we are observing, i.e., the theory is incomplete.
- Physical laws are not constant. e are looking at very distant objects, and seeing them in the distant past. Perhaps universal constants are not, in fact, constant across large spans of space and/or time.
So now they've discovered a galaxy where the kludge factor of dark matter is not needed. Maybe this will prompt more cosmologist to consider the alternatives...
Actually this evidence supports Dark Matter and contradicts those two theories quite nicely. They both describe universal phenomena -- if the laws of gravity are different, or physical laws are changing the every distant galaxy should show the same anomalous motion. On the other hand if the usual anomalous motion is due to "stuff" (dark matter) then it's not very surprising that some rare event (like a collision) could have separated this galaxy from its original dark matter.
Rotational speeds have been explained rather nicely by other theories, but dark matter/energy has become astronomical doctrine so those better-fitting yet alternate theories get scoffed at.
Can you give a RECENT example of another theory that explains rotational speeds and doesn't contradict any other observations?
Does it also explain ANY of the other things that Dark Matter explains?
You're confused. Dark matter and dark energy aren't concrete things. They're placeholders for the remainders that don't fit the currently understood data. They are the X and the Y in an equation we haven't yet solved. X and Y are in fact the "only" solutions to the equation, because that's a tautology. The solution to the equation is the solution to the equation. But because we don't know what they are they could turn out to be almost anything, or a combination of things. There are a lot of theories as to what they might be, but none of them is definite, and none will be until we gather more data.
But you can say that for anything outside your own head. Everything in the entire universe is just a placeholder to fit a set of observations. At some point we decide the the observations are detailed and consistent enough that we'll stop worrying about this and talk as if the object really exists. If you look at recent data, dark matter has reached that point. Multiple approaches give a pretty consistent idea of where it is, how much of it there is, and some aspects of how it behaves. Dark energy not so much, yet.
Two problems: (1) we can measure the rotational velocities (2) The galaxies are old enough to have rotated 50 or so times and the spiral structure is still there.
What makes it even more kludgy is that this dark matter is supposed to make up a significant percentage of the universe. Except there is *NONE* in our solar system or it's immediate vicinity. If there was any dark matter locally then General Relativity would not explain the planets orbits around the Sun with such precision because it's does so using only visible matter.
This is a huge problem for dark matter because it presumes that our solar system is somehow very special, which is frankly too fantastical.
This is just wrong. This paper: https://arxiv.org/pdf/1404.193... (which also has a lot of interesting background) collects estimates of the density of dark matter in this part of the galaxy, most of which are around 0.01 solar masses/ cubic parsec (around 10^-21 kilograms/m^3). So even if the solar system was pervaded by dark matter of this density it would make no measurable difference to anything. For example the entire sphere up to Earth's distance from the Sun would contain about a billion tons of dark matter, the same as the mass of a extra 1 km diameter asteroid.
There will still be a role for a power grid to redistribute power over space and time to match supply and demand even if a significant amount is produced, stored and consumed locally. It will need a much more sophisticated pricing, quality of service and regulatory model, but it will still be very much essential infrastructure.
It's out of fuel, not power.
Ion drives (or possibly electrodynamic tethers) kind of solve the problem of changing orbits cheaply, if you're not in a hurry.
DIfferent observers would calculate different lengths of time (and distances in space) between the sun going dark and the last light from the Sun passing the Earth.
In relativity, none of these observers is "special". All their calculations are equally correct. What they would agree on is the speed that that the light from the Sun was travelling at. So some might see the light taking 1 second to travel 300 000 km from the Sun to the Earth, others would see it taking about 8 minutes to travel 150 000 000 km (no one would see anything longer than that).
You could take a look at what Software Carpentry https://software-carpentry.org... teach. They cover relatively practical skills like version control, regression tests, etc. which are still a big step forward for many research programmers.
At a more conceptual level you are aiming towards "abstraction" and "separation of concerns". Self-taught academic programmers are usually quite good at getting individual methods to work, but hopeless designing software so that changes are localised.
This is about the details of how the explosion happens. A star is a pretty big thing and it does not all explode at once. The explosion starts pretty far in and has to somehow get through or past the outer layers of the star before we can see it. The details of how that happens are very unclear.
You can combine multiple mirrors within a single telescope, but you have to keep them aligned to enormous accuracy (50nm or so) so you still need a massive framework.
You can combine multiple telescopes by actually steering the incoming light to a meeting point and interfering it, but it's incredibly hard to do. Everything needs to be super stable.
You can't get (much) more detail by combining multiple digital images. You can get a bigger image, or a "deeper" image (one that shows fainter objects) but not a more detailed one.