APOD: Confirmed Muon Wobble Remains... (2021 Apr 13)

[APOD Robot]

Confirmed Muon Wobble Remains Unexplained

Explanation: How fast do elementary particles wobble? A surprising answer to this seemingly inconsequential question came out of Brookhaven National Laboratory in New York, USA in 2001, and indicated that the Standard Model of Particle Physics, adopted widely in physics, is incomplete. Specifically, the muon, a particle with similarities to a heavy electron, has had its relatively large wobble under scrutiny in a series of experiments known as g-2 (gee-minus-two). The Brookhaven result galvanized other experimental groups around the world to confirm it, and pressured theorists to better understand it. Reporting in last week, the most sensitive muon wobble experiment yet, conducted at Fermi National Accelerator Laboratory (Fermilab) in Illinois and pictured here, agreed with the Brookhaven result. The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known. Alternatively, it may indicate that flaws exist in difficult theoretical prediction calculations. Future runs at Fermilab's g-2 experiment will further increase precision and, possibly, the statistical difference between the universe we measure and the universe we understand.

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[WWW]

OK, muons wobble more than predicted.
That may well be big news for the realm of quantum physics.
Wake me up when we get back to an "Astronomy" Picture of the Day.

[Chris Peterson]

OK, muons wobble more than predicted.
That may well be big news for the realm of quantum physics.
Wake me up when we get back to an "Astronomy" Picture of the Day.

You are perhaps unaware of the degree to which QM underlies much of our astronomical knowledge. Quantum physics and astrophysics are inseparable.

[De58te]

It is good to hear that the 'Muon Wobble Remains Unexplained' hypothesis has now been confirmed. Good work. The world previously was a much scarier place when the unexplained Muon wobble was unconfirmed.

[PolishBear]

OK, muons wobble more than predicted.
That may well be big news for the realm of quantum physics.
Wake me up when we get back to an "Astronomy" Picture of the Day.

Well this is a rather dismaying comment. This kind of muon research is inextricably linked to astrophysics. I thought this photo was perfectly appropriate for an astronomy site.

As Brian Greene has pointed out: "From our lonely point in the cosmos, we have through the power of thought been able to peer back to a brief moment after the beginning of the universe."

https://www.youtube.com/watch?v=9Cd36WJ79z4

[King_nothing]

"The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known". Dark matter?

[orin stepanek]

Guess I'm not very smart after all!

This pooch is pretty smart;

So is this one!


I must confess i watched all the links; and was very impressed even though a lot ot it was pretty deep! I'm glad that Science is ever moving forward!

[NCTom]

As a believer in a Creator-God and who also believes he gave us a brain to use, this kind of research is essential to move toward a greater understanding of the big picture. That includes the most elemental particles to the strongest of forces driving motion in our universe. Limited as we are with a rather tiny observation point fixed on this grain of matter in one planetary system in one galaxy in one small spot of the totality, we have a lot yet to learn. Einstein tried but he had neither today's tools nor a long enough life. The more we research and learn the more we confirm his theories on the interconnectedness of the very small and the very large. A fourteen billion year-old universe, or however old it is, can create a lot of big and little things. We need bigger colliders.

[E Fish]

It looks like the Stargate fell over!

This QM stuff is so fascinating to me. My study of physics didn't get beyond introductory modern physics, but I have a stack of books on QM that are waiting for me to get to them. (After I read my book on the women of the Harvard Observatory at the beginning of the 20th century. )

What does it really mean when a muon wobbles? Is it like spin? I read a description of particle spin before. It said, "Imagine a marble spinning like a top, only it's not a marble and it's not spinning."

[Chris Peterson]

It looks like the Stargate fell over!

This QM stuff is so fascinating to me. My study of physics didn't get beyond introductory modern physics, but I have a stack of books on QM that are waiting for me to get to them. (After I read my book on the women of the Harvard Observatory at the beginning of the 20th century. :) )

What does it really mean when a muon wobbles? Is it like spin? I read a description of particle spin before. It said, "Imagine a marble spinning like a top, only it's not a marble and it's not spinning." :)

These terms like "spin" and "wobble" and "angular momentum" used in QM were chosen because they are analogous in some ways to those things in macroscopic objects, as we see in the mathematics that seems to describe their behavior. But these particles are probably not "spinning" in the physical sense we picture for the sort of objects we can see. Even the term "particle" is complex in QM, frequently being represented by a field, and not an "object" at all. At the scale of QM, behavior is typically described by integer and half-integer values (hence "quantum") and it's best to not rely on the names given those quantities (like "spin") to understand what is going on.

[bystander]

... it's best to not rely on the names given those quantities (like "spin") to understand what is going on.

So subatomic particles don't actually come in flavors?

[neufer]

OK, muons wobble more than predicted.
That may well be big news for the realm of quantum physics.
Wake me up when we get back to an "Astronomy" Picture of the Day.

Well this is a rather dismaying comment. This kind of muon research is inextricably linked to astrophysics. I thought this photo was perfectly appropriate for an astronomy site. As Brian Greene has pointed out: "From our lonely point in the cosmos, we have through the power of thought been able to peer back to a brief moment after the beginning of the universe." https://www.youtube.com/watch?v=9Cd36WJ79z4

"The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known".

Dark matter

• http://asterisk.apod.com/viewtopic.php? ... ac#p312304
  http://asterisk.apod.com/viewtopic.php? ... ac#p312433

• The anomalous magnetic moment of the muon includes three parts:

---

---

represents the photon and lepton loops, and

---

represents the W boson, Higgs boson and Z boson loops;
both terms can be calculated precisely from first principles.

---

represents hadron loops & cannot be calculated accurately from theory alone.

• The current experimental value and uncertainty is:

---

Diddy Wishingwell : Barn Dance playset

---

Weebles wobble, but they don't fall down

---

<<The catchphrase "Weebles wobble, but they don't fall down" was used in advertising during the 1970s and successive relaunches in the early 2000s. Weebles is a range of children's roly-poly toys originating in Hasbro's Playskool division on July 23, 1971.

A Weeble is shaped like an egg—in order for the physics principles to work as intended, the shape must have a bottom which is a more or less smooth (unfaceted) hemisphere (to allow the Weeble to roll) and from the central vertical axis the shape must be nearly cylindrically symmetrical (that is, any plane cut through the vertical axis line must produce close to the same profile). Next, the shape must be filled with two basic types of unmixed solids, and the volume of the lighter solid must be greater than that of the heavier solid. Next, the overall shape must have constant positive curvature. Next, the relationship between the heavy solid and the light solid must be such that any orientation of the object off of the vertical axis line must cause the object's centroid to raise and to become offset. Lastly, the object must have only one position in which it can achieve stable mechanical equilibrium.

Combining these characteristics produces a basic Weeble. In theory, it is not possible to have a Weeble with a centroid that is too low to achieve a stable mechanical equilibrium. >>

[Chris Peterson]

... it's best to not rely on the names given those quantities (like "spin") to understand what is going on.

So subatomic particles don't actually come in flavors? :mrgreen:

Or colors, either.

[Chris Peterson]

"The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known". Dark matter?

I think that the existence of dark matter has long pointed to an incompleteness in the Standard Model. So this finding doesn't surprise me. While some sensational news stories have suggested this discovery will lead to a "whole new physics", by guess is that the Standard Model remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

[neufer]

"The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known".

Dark matter?

I think that the existence of dark matter has long pointed to an incompleteness in the Standard Model. So this finding doesn't surprise me. While some sensational news stories have suggested this discovery will lead to a "whole new physics", by guess is that the Standard Model remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

I think that the "anomalous" precession of the perihelion of Mercury has long pointed to an incompleteness in the Newtonian theory of gravity.

While some sensational news stories have suggested this "anomaly" will lead to a "whole new physics", my guess is that the Newtonian theory of gravity remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

• Perihelion precession of Mercury

<<Under Newtonian physics, a two-body system consisting of a lone object orbiting a spherical mass would trace out an ellipse with the center of mass of the system at a focus. The point of closest approach, called the periapsis (or, because the central body in the Solar System is the Sun, perihelion), is fixed. A number of effects in the Solar System cause the perihelia of planets to precess (rotate) around the Sun. The principal cause is the presence of other planets which perturb one another's orbit. Another (much less significant) effect is solar oblateness.

Mercury deviates from the precession predicted from these Newtonian effects. This anomalous rate of precession of the perihelion of Mercury's orbit was first recognized in 1859 as a problem in celestial mechanics, by Urbain Le Verrier. His reanalysis of available timed observations of transits of Mercury over the Sun's disk from 1697 to 1848 showed that the actual rate of the precession disagreed from that predicted from Newton's theory by 38″ (arcseconds) per tropical century (later re-estimated at 43″ by Simon Newcomb in 1882). A number of ad hoc and ultimately unsuccessful solutions were proposed, but they tended to introduce more problems.

In general relativity, this remaining precession, or change of orientation of the orbital ellipse within its orbital plane, is explained by gravitation being mediated by the curvature of spacetime. Einstein showed that general relativity agrees closely with the observed amount of perihelion shift. This was a powerful factor motivating the adoption of general relativity.

Although earlier measurements of planetary orbits were made using conventional telescopes, more accurate measurements are now made with radar. The total observed precession of Mercury is 574.10″±0.65 per century relative to the inertial ICRF. This precession can be attributed to the following causes:

Code: Select all

Sources of the precession of perihelion for Mercury

Amount (arcsec/Julian century) 	Cause
----------------------------------------------------------------------
  532.3035 	Gravitational tugs of other solar bodies
  042.9799 	Gravitoelectric effects (Schwarzschild-like), a General Relativity effect
  000.0286 	Oblateness of the Sun (quadrupole moment)
 −000.0020 	Lense–Thirring precession

  575.31 	Total predicted

  574.10±0.65 	Observed

[neufer]

... it's best to not rely on the names given those quantities (like "spin") to understand what is going on.

So subatomic particles don't actually come in flavors?

Or colors, either.

If subatomic particles actually come in colors Ann would have posted about them by now.

[Chris Peterson]

"The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known".

Dark matter?

I think that the existence of dark matter has long pointed to an incompleteness in the Standard Model. So this finding doesn't surprise me. While some sensational news stories have suggested this discovery will lead to a "whole new physics", by guess is that the Standard Model remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

I think that the "anomalous" precession of the perihelion of Mercury has long pointed to an incompleteness in the Newtonian theory of gravity.

While some sensational news stories have suggested this "anomaly" will lead to a "whole new physics", my guess is that the Newtonian theory of gravity remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

Yes. My point exactly. Newtonian physics was tweaked, not replaced.

[neufer]

I think that the existence of dark matter has long pointed to an incompleteness in the Standard Model. So this finding doesn't surprise me. While some sensational news stories have suggested this discovery will lead to a "whole new physics", by guess is that the Standard Model remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

I think that the "anomalous" precession of the perihelion of Mercury has long pointed to an incompleteness in the Newtonian theory of gravity.

While some sensational news stories have suggested this "anomaly" will lead to a "whole new physics", my guess is that the Newtonian theory of gravity remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

Yes. My point exactly. Newtonian physics was tweaked, not replaced.

Newtonian physics was clearly replaced!

However, it remains an excellent approximation.

The same will happen with the Standard Model.

(That has been the story of physics for many years now.)

[Chris Peterson]

I think that the "anomalous" precession of the perihelion of Mercury has long pointed to an incompleteness in the Newtonian theory of gravity.

While some sensational news stories have suggested this "anomaly" will lead to a "whole new physics", my guess is that the Newtonian theory of gravity remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

Yes. My point exactly. Newtonian physics was tweaked, not replaced.

Newtonian physics was clearly replaced!

However, it remains an excellent approximation.

The same will happen with the Standard Model.

(That has been the story of physics for many years now.)

Newtonian physics was not replaced. Newtonian physics is <i>exactly</i> the output of Einsteinian physics when you are dealing with zero speed and inertial frames.

I don't think we'll see a major change in the Standard Model. We'll see some more boxes filled in.

[johnnydeep]

"The unexpected wobble rate may indicate that an ever-present sea of virtual particles includes types not currently known". Dark matter?

I think that the existence of dark matter has long pointed to an incompleteness in the Standard Model. So this finding doesn't surprise me. While some sensational news stories have suggested this discovery will lead to a "whole new physics", by guess is that the Standard Model remains fundamentally accurate, and what we will see is adjustments, not replacements. That has been the story of physics for many years now.

I fully expect Michio Kaku to be breathlessly proclaiming this to be a "game changer" any day now, if he hasn't already. (Yes, I know he has many true research creds, but he always seems to lean to the sensational side of things whenever I see him trotted out as an expert on TV.)

[johnnydeep]

As a believer in a Creator-God and who also believes he gave us a brain to use, this kind of research is essential to move toward a greater understanding of the big picture. That includes the most elemental particles to the strongest of forces driving motion in our universe. Limited as we are with a rather tiny observation point fixed on this grain of matter in one planetary system in one galaxy in one small spot of the totality, we have a lot yet to learn. Einstein tried but he had neither today's tools nor a long enough life. The more we research and learn the more we confirm his theories on the interconnectedness of the very small and the very large. A fourteen billion year-old universe, or however old it is, can create a lot of big and little things. We need bigger colliders.

I used my brain to conclude long ago that there is no Creator-God. Should he or she - contrary to all reason, logic and evidence - actually exist, I trust he or she won't hold this against me in the after life.

[neufer]

Click to play embedded YouTube video.

Newtonian physics is exactly the output of Einsteinian physics
when you are dealing with zero speed and inertial frames.

Newtonian physics is exactly the output of Einsteinian physics when
you are dealing with zero speed, zero dimensions & inertial frames.

Quantum Mechanics tells us that
one cannot have both zero speed & zero dimensions.

I don't think we'll see a major change in the Standard Model.
We'll see some more boxes filled in.

[neufer]

Touched by His Noodly Appendage

---

I used my brain to conclude long ago that there is no Creator-God. Should he or she - contrary to all reason, logic and evidence - actually exist, I trust he or she won't hold this against me in the after life.

I used my brain to conclude long ago that there is no after life.

[johnnydeep]

Touched by His Noodly Appendage

---

I used my brain to conclude long ago that there is no Creator-God. Should he or she - contrary to all reason, logic and evidence - actually exist, I trust he or she won't hold this against me in the after life.

I used my brain to conclude long ago that there is no after life.

Oh contraire! There is indeed an "after life". It's just that when we die, we will no longer be participating in it.

[neufer]

Touched by His Noodly Appendage

---

I used my brain to conclude long ago that there is no Creator-God. Should he or she - contrary to all reason, logic and evidence - actually exist, I trust he or she won't hold this against me in the after life.

I used my brain to conclude long ago that there is no after life.

Oh contraire! There is indeed an "after life".

It's just that when we die, we will no longer be participating in it.

• Whether we participate or not is really a decision to be best left
  in FSM's Noodly Appendages since we will no longer have Free Will.

---

Afterlife: The Pastafarian conception of Heaven includes a beer volcano and a stripper (or sometimes prostitute) factory. (Pastafarian Hell is similar, except that the beer is stale and the strippers have STDs.)

Creation: The central creation myth is that an invisible and undetectable Flying Spaghetti Monster created the universe "after drinking heavily". According to these beliefs, the Monster's intoxication was the cause for a flawed Earth [and the muon wobble]. Furthermore, according to Pastafarianism, all evidence for evolution was planted by the Flying Spaghetti Monster in an effort to test the faith of Pastafarians. When scientific measurements such as radiocarbon dating are taken, the Flying Spaghetti Monster "is there changing the results with His Noodly Appendage".>>