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Why are black holes stable against their own gravity?

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Why are black holes stable against their own gravity?


Why are Black Holes stable against their own gravity?
Fig. 1. A Black Hole of mass M has an interior negative constant scalar curvature R, with a radius r0 given by the Schwarzschild solution (r0 = 2GM/c2 , where c is the speed of light and G is Newton’s gravitational constant). This creates an outward pressure PS exactly canceling the inward pressure PM from the Black Hole self-gravity trying to compress the object. R is discontinuous at the Horizon. There is no surface tension. Credit: Reports in Advances of Physical Sciences (2023). DOI:10.1142/S2424942423500019

Neutron stars are timelike matter with a maximum mass of about 2.34 solar masses in quantum chromodynamics (the strong color force). Black holes are spacelike matter that have no maximum mass, but a minimum mass of 2.35 solar masses. Indeed, black holes have been identified with millions or billions of solar masses.

All timelike matter is causal, while black hole spacelike matter is acausal. Acausal spacelike matter has no identifiable particle states (everything is off mass-shell in the spacelike region), no Pauli principle, no equations of motion, no equation of hydrostatic stability, no equations of state, no entropy, no temperature, no Planck constant, no Boltzmann constant, no finite temperature quantum field theory.

The only quantities a black hole has are gravitational invariants, which are observables at infinity and the scalar curvature R. Functions of gravitational invariants are also gravitational invariants such as its volume, area, radius, etc.

Gravitational manifolds are metric spaces that have isometric symmetries, and these gravitational invariants are invariants under these symmetries. If the metric space is Minkowski space, the isometric symmetries are just the familiar Poincare group.

Black holes are stable objects with no maximum mass

The black hole pressures—PS, the outward pressure keeping it inflated from the negative scalar curvature, and PM the inward pressure from self-gravity trying to compress it—are gravitational invariants. In the proof that PS = -PM , it is shown that the equilibrium is also stable and a universal black hole constant emerges F = 3c4/4G = 9.077…x1043 N.

All black holes have the same force constant F inflating them, independent of black hole mass. It is this new black hole universal constant that explains why black holes have no maximum mass.

There are two immediate consequences of this universal force constant:

(1) The largest pressure in the universe, Puniverse, is a physical observable and calculable. The smallest black hole has the highest pressure in the universe. Using the previously mentioned estimated minimum 2.35 solar mass, one obtains Puniverse = 1.5183…x 1035 N/m2. This is an incomprehensibly large value, so we can compare it to the estimated center pressure of Jupiter PJupiter = 650 x 106 pounds/in2 (NASA website—uses British units), giving Puniverse/PJupiter = 3.3878…x1022, still beyond human comprehension.

(2) There exists an area law for black holes to coalesce, but it is not Hawking’s guess and has nothing whatever to do with entropy. In order for two coalescing black holes to form with pressures P1 and P2 in the volume, leaving a remnant with pressure P3, it is required that P1+P2 > P3, otherwise the remnant cannot exist. Since the pressures are P = F/area, with universal force constant F, this gives the actual black hole coalescing area law, involving reciprocal areas 1/A1 + 1/A2 > 1/A3. The available gravitational wave data is consistent with this reciprocal coalescing area law. The existence of the universal black hole constant controls the coalescence of black holes.

Why are black holes stable against their own gravity?
Fig. 2. Fake BH singularity due to the miss-appropriation of the causal Einstein equations of motion to acausal BH. Units are G = c = 1. Credit: Reports in Advances of Physical Sciences (2024). DOI: 10.1142/s242494242450004x

Question of black hole singularities

Applying causality to acausal spacelike matter always leads to contradictions. The widely quoted statement that black holes have a singularity is based on the misapplication of the causal Einstein equations of motion to acausal black holes, producing a fake singularity, see figure 2.

This equation is a contradiction, because the scalar curvature is a gravitational invariant on the left-hand side, but the right-hand side has spherical coordinates, which are not gravitationally invariant. In the article published in Reports in Advances of Physical Sciences, it is thus proved that black holes have no singularities.

Contradictions always arise if causal physics is applied to black hole spacelike matter

There are contradictions that arise if causal finite temperature quantum field theory is misappropriated to acausal spacelike black holes: In a commonly cited reference, Hawking did this exact misappropriation and stated that black holes have a temperature and evaporate away their mass, reaching the vacuum state.

Where is the contradiction that we expect when causal physics is applied to acausal spacelike black holes? If black holes truly radiated, their mass would indeed approach zero, but as Figure 1 shows, their negative scalar curvature R does not go to zero, but instead goes to negative infinity: The black hole end state is not the required vacuum state R = 0. This is the contradiction that arises from misappropriated causal finite temperature field theory to acausal spacelike matter.

Renormalization of the scalar curvature R

One of the goals in general relativity is the renormalization of R in four-dimensional spacetime. It is shown in a 2018 article that the renormalization of R in finite temperature quantum field theory satisfies the same theorem as the renormalization of the thermodynamic potential.

Both quantities are physical observables that have no “legs” (meaning no external Green functions) in Feynman diagrams. The “infamous” prediction in quantum field theory that the electroweak vacuum energy density is 10120 orders of magnitude larger than the experimental vacuum energy density is a false statement, because this constant term cancels out in the renormalization theorem for the thermodynamic potential.

Finally, one can say that the planet Jupiter, because of causality, is inarguably a much more complicated object than an acausal black hole.

This story is part of Science X Dialog, where researchers can report findings from their published research articles. Visit this page for information about Science X Dialog and how to participate.

More information:
P. D. Morley, Why are Black Holes Stable Against Their Own Gravity? Reports in Advances of Physical Sciences (2024). DOI: 10.1142/S242494242450004X

Dr. Peter Morley is a theoretical physicist. A partial listing of his papers can be found here: inspirehep.net/authors/996788

Citation:
Why are black holes stable against their own gravity? (2024, September 6)
retrieved 6 September 2024
from https://phys.org/news/2024-09-black-holes-stable-gravity.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





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Future of Google search rests with judge who will strip away monopoly power: Q&A with antitrust expert

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Future of Google search rests with judge who will strip away monopoly power: Q&A with antitrust expert


Google search
Credit: Pixabay/CC0 Public Domain

Google’s future as provider of the world’s most dominant search engine rests in the hands of a federal court judge who last month ruled the company has a monopoly on internet search.

In a hearing in U.S. District Court for the District of Columbia, Judge Amit Mehta will start to strip Google of its monopoly power after previously finding Google’s distribution deals with companies that make Google the default search engine on devices, including Apple, violated federal antitrust law.

Federal government lawsuits against Silicon Valley’s top three technology titans and Seattle-based Amazon, which all amassed colossal market dominance and riches with little pushback from authorities, signal a shift toward bipartisan and public mistrust of the role the companies play in society and the U.S. economy.

UC Berkeley law school adjunct professor and professional mediator Christopher Hockett, an antitrust expert who has closely followed the Google search case, answered questions in an interview last month about the Google search lawsuit by the U.S. Justice Department, and how it fits with the other court actions.

Q: What would search would look like if Google had competition?

A: Google has had a very high and very stable market share—since 2009 it’s been over 80% in general search service. The assumption behind Judge Mehta’s ruling is the world would be better.

Q: Why did this lawsuit come about after years of Google’s dominance in search?

A: This case was brought in the waning months of the Trump administration, in October 2020. It kind of underlines the bipartisan interest in prosecuting these claims against at least Google if not the whole Big Tech world.

On the left, there’s hostility toward the tech companies because they’re led by tech moguls who have lots of money and seem to act with impunity, and at least according to that view, they are presiding over monopolies that don’t have consumers’ interests at heart.

On the right, the political narrative is that Big Tech players, especially social media players, are biased against conservative points of view and they’re censoring them. Although the services of most of these companies remain extremely popular, the companies and the people that run them are, with the public, somewhat less popular.

Q: Do the Justice Department’s antitrust cases against Google—over search and ads, and Apple over smartphones, and the U.S. Federal Trade Commission’s antitrust cases against Amazon over e-commerce and Meta over its acquisitions of Instagram and WhatsApp—all signal a backlash against Big Tech?

A: At a broad level, yes. It’s particularly salient in the case of social media companies where there’s a souring public mood about their effects on society and how we get along with each other. But (the cases) are all going to run into antitrust precedent that is not particularly friendly to monopolization claims. The Supreme Court in particular has been very trusting of the market process in correcting any mistakes in under-enforcement of monopolization.

Q: What will happen Friday in the first hearing on remedies to Google’s monopoly?

A: I’d be surprised if (Mehta) got into the ideas for remedies substantively. He’s going to set out a schedule for the parties to weigh in on.

Q: What are Mehta’s options for remedies?

A: There’s been a lot of talk about a breakup of some kind. We’ll see soon, probably, whether that is something the judge is interested in and why. It could be divesting the Android operating system—he could say, “You need to sell that off, or split it off somehow”—or (divesting) Chrome or Google’s web indexing capacity. The judge found a problem with Google’s distribution agreements and it seems like it would be more straightforward to address those with . . . an injunction that says, “You can’t pay for default status.”

Q: What’s the process after Friday?

A: The Justice Department (will) come forward with remedies that it thinks are in order, then Google will respond. I would assume it would take several months.

Q: How long will it take for Mehta to issue an order intended to end Google’s monopoly?

A: My guess is a month or two. He’ll take as long as he needs because it’s an important case.

Q: Do you expect Google to appeal?

A: Yes. They won’t argue everything—it won’t be a kitchen-sink thing. One of the things they argued in the case … is that there was competition for the Apple default because Apple would open up that opportunity to providers like Google and Bing. Google got that opportunity because it offered the highest prices. I assume that that argument is going to be reiterated on appeal.

This is a situation that raises the question, “Can you be liable for monopolization when 90% of users want your product because it’s the best product, and the device makers want your product?” If Judge Mehta orders remedies that (Google) doesn’t want to live with before the appeal, it will ask Judge Mehta to suspend the imposition of remedies. If he says no, they will ask the court of appeal for the same thing.

Q: How long would the appeal to the D.C. Circuit take, and could it go to the U.S. Supreme Court?

A: A year, probably. Then the D.C. circuit will take whatever time it takes. This kind of case is not guaranteed to get to the Supreme Court because they have a discretionary appeal system (but) it seems likely that unless they resolve the case by settlement while the proceedings are pending that it would go to the Supreme Court. They could reach an agreement on remedy at any point in these proceedings.

Q: If the case goes to the Supreme Court, when do you think a ruling would be issued?

A: Between two and three years from now.

2024 MediaNews Group, Inc. Distributed by Tribune Content Agency, LLC.

Citation:
Future of Google search rests with judge who will strip away monopoly power: Q&A with antitrust expert (2024, September 6)
retrieved 6 September 2024
from https://techxplore.com/news/2024-09-future-google-rests-monopoly-power.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.





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Just how dangerous is Great Salt Lake dust? New research looks for clues

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Just how dangerous is Great Salt Lake dust? New research looks for clues


Just how dangerous is Great Salt Lake dust? New research looks for clues
Evan Bush, NBC News Dust researcher Kevin Perry poses with his fat bike and a PI-SWERL machine, which can measure wind erosion and dust emission. Credit: University of Utah

As Utah’s Great Salt Lake shrinks, exposing more of its playa, concerns grow about the dust the dry lakebed emits. But scientists lack the data to fully understand what pollutants are present in these airborne sediments.

Researchers from the University of Utah are attempting to get a handle on this question and the latest findings are concerning.

Sediments in the lake’s exposed playa are potentially more harmful than other major dust sources affecting the Wasatch Front’s air quality, according to a study published online in the journal Atmospheric Environment, titled “Assessing the oxidative potential of dust from Great Salt Lake.”

These sediments, when aerosolized, show higher levels of reactivity and bioavailability when compared to sediments collected from other spots upwind of Utah’s major population center along the Wasatch Front. Chemical analysis also indicated the presence of numerous metals, and levels of arsenic and lithium that exceed the U.S. Environmental Protection Agency’s soil residential regional screening levels.

“You’re talking about a very large dust source located next to a very large population, and you’ve got elevated levels of manganese, iron, copper and lead. Lead is a concern for developmental reasons,” said senior author Kerry Kelly, a professor of chemical engineering.

“Manganese, iron and copper, these are transition metals and are known to be very irritating to your lungs. Once you get irritation, that can lead to this whole inflammatory response. And that’s part of the problem with particulate matter and it’s adverse health effects like asthma.”

The Great Salt Lake is a terminal body receiving runoff from a vast drainage basin spanning northern Utah and parts of three other states. Metals from natural sources and human disturbances are pushed into the lake from inflows or atmospheric deposition, and these materials accumulate in the lakebed. The potential for harmful dust pollution has become a priority for Utah state officials, who issued a list of priorities aimed at tackling the problem.

Another recent study led by sociology professor Sara Grineski found dust from the lakebed disproportionately affects disadvantaged neighborhoods in Salt Lake County.

In a separate forthcoming study led by U biologist Michael Werner’s lab, another team of researchers characterized levels of toxic metals deposited in submerged lakebed sediments sampled during the lake’s record low-water year of 2021, noting how these levels have changed since the years of Utah’s mining era.

Concentrations of some metals, such as lead and zinc, appear to have decreased, likely a reflection of the decline in the region’s mining activity, while mercury levels surprisingly have increased.

Researchers cautioned that they can’t conclude whether these pollutants are actually being blown into populated areas during wind events because the monitoring equipment to capture that dust has yet to be adequately deployed downwind of the lake. Most high-wind events arrive from the southwest, blowing for several hours off the lake north into Weber or Box Elder County, before shifting to the south as the front passes through.

To conduct the study, Kerry Kelly’s lab, which specializes in air quality, teamed up with researchers in the U’s College of Science. They examined previously collected sediment samples from the Great Salt Lake, comparing them with sediments from other dust sources in the Great Basin, namely Sevier Lake, Fish Springs Lake and West Desert in western Utah and Tule Lake in northeastern California. These places are known to contribute to dust pollution reaching Salt Lake City.

In recent years, co-author Kevin Perry, a professor of atmospheric sciences, has systematically gathered exposed lakebed sediments, logging hundreds of miles on a bike. His prior research has identified “hotspots” on the playa that appear to be enriched with potentially toxic elements.

Only 9% of the exposed lakebed, or 175 square kilometers (about 43,000 acres), is emitting dust from areas where lakebed crusts are disturbed, according to Perry. The rest of the playa is covered in a natural hardened layer that keeps the sediments in place.

Perry’s ongoing research examines what happens to the playa crusts over time. He said his initial findings indicate the broken layers reset fairly easily, suggesting the playa’s threat to air quality may not be as dire as previously thought.

The latest study is the first to analyze the dust’s “oxidative potential,” a measure of its ability to react with oxygen.

“When you breathe in something that’s really reactive, it’s going to interact with the cells inside your lungs and it’s going to cause damage,” Kelly said.

In the lab, the team aerosolized the sediment samples to isolate the particles that are small enough to inhale and lodge in lung tissue, those smaller than 10 micrometers or PM10.

These particles were captured on filters and further analyzed using a method called inductively coupled mass plasma mass spectrometry to determine their elemental makeup and other tests to determine their oxidative potential (OP) and bioaccessibility.

“We devised a way to dissolve the metals using increasingly caustic acids to figure out at what level these metals leaching from the particles,” Perry said. “It turns out that the dust from Great Salt Lake has more leachable metals that are bioavailable than we would wish.”

Meanwhile, high OP was detected in dust associated with certain metals, including copper, manganese, iron and aluminum.

More information:
Reuben Attah et al, Assessing the oxidative potential of dust from great salt Lake, Atmospheric Environment (2024). DOI: 10.1016/j.atmosenv.2024.120728

Provided by
University of Utah

Citation:
Just how dangerous is Great Salt Lake dust? New research looks for clues (2024, September 6)
retrieved 6 September 2024
from https://phys.org/news/2024-09-dangerous-great-salt-lake-clues.html

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Dutch match US export curbs on semiconductor machines

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Dutch match US export curbs on semiconductor machines


ASML produces cutting-edge machines used to make semiconductors
ASML produces cutting-edge machines used to make semiconductors.

The Dutch government announced Friday broader restrictions on exports of semiconductor-making machines produced by sector heavyweight ASML, aligning itself with US curbs on technology at the center of trade tensions with China.

The measure, which will take effect on Saturday means ASML will be able to apply for export licenses directly with the Dutch authorities instead of the US government to export the equipment outside the European Union.

The Netherlands had previously not applied restrictions on certain equipment that was under US export controls, forcing the Dutch company to request licenses from US authorities.

“I’ve made this decision for reasons of security,” foreign trade minister Reinette Klever said in a statement on the measure.

“We see that technological advances have given rise to increased security risks associated with the export of this specific manufacturing equipment, especially in the current geopolitical context,” Klever said, without directly mentioning China.

The new restrictions will apply to “more types of equipment” on top of curbs that have been in force since September 2023, the government said.

ASML said in a statement that the measure “will harmonize the approach for issuing export licenses”.

“Since this is a technical change, this announcement is not expected to have any impact on our financial outlook for 2024 or for our longer-term scenarios,” the company said.

Shares in ASML were down 1.5 percent in early afternoon trading on the Amsterdam stock exchange.

The Netherlands and Japan have previously joined the United States in imposing certain export restrictions on advanced chip-making equipment aimed at preventing China from acquiring sensitive inputs that could be used in cutting-edge weapons and tech such as AI.

Responding to the latest measures, the Chinese foreign ministry said, “China has always been opposed to this wrong practice of politicizing normal economic and trade relations and abusively linking them to issues of national security.”

“Trying to set up a technological blockade against China and artificially disrupt the stability of global production and supply chains will only lead to damage to its own interests,” it said in a statement to AFP.

The ministry added that China would “closely follow” developments and “resolutely safeguard its legitimate rights and interests”.

‘Unique’ position

The Dutch government said Friday the equipment can be used to produce advanced semiconductors which “in turn play a key role in advanced military applications.”

“Thus, the uncontrolled export of this type of manufacturing equipment has implications for the Netherlands’ security interests,” the statement said.

ASML said the updated license requirement will apply to its TWINSCAN NXT:1970i and 1980i DUV (deep ultraviolet) immersion lithography systems, which print the tiny elements of a microchip.

Dutch export licenses already existed for other types of DUV systems as well as its extreme ultraviolet (EUV) lithography machines, which are used to make more advanced semiconductors.

The government said Friday it would “assess applications on a case-by-case basis, so this is not an export ban”.

The Netherlands has a unique, leading position in this area. This entails certain responsibilities, which we take seriously,” Klever said.

“We have proceeded in a careful and targeted manner, so as to minimize the disruption to global trade flows and value chains,” she said.

The move comes a day after the United States tightened its own restrictions on certain technology.

The US Commerce Department said Thursday it was implementing worldwide export curbs on specific types of items such as quantum computers and machines needed to make advanced semiconductor devices.

© 2024 AFP

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Dutch match US export curbs on semiconductor machines (2024, September 6)
retrieved 6 September 2024
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Video game performers reach agreement with 80 video games on AI terms

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Video game performers reach agreement with 80 video games on AI terms


Video game performers reach agreement with 80 video games on AI terms
Actor Sena Bryer, second from left, joins other demonstrators in a SAG-AFTRA video game actor strike picket line outside Warner Bros. Studios on Wednesday, Aug. 28, 2024, in Burbank, Calif. Credit: AP Photo/Chris Pizzello

After striking for over a month, video game performers have reached agreements with 80 games that have signed interim or tiered budget agreements with the performers’ union and accepted the artificial intelligence provisions they have been seeking.

Members of the Screen Actors Guild-American Federation of Television and Radio Artists began striking in July after negotiations with game industry giants that began more than a year and a half ago came to a halt over AI protections. Union leaders say game voice actors and motion capture artists’ likenesses could be replicated by AI and used without their consent and without fair compensation.

SAG-AFTRA announced the agreements with the 80 individual video games on Thursday. Performers impacted by the work stoppage can now work on those projects.

The strike against other major video game publishers, including Disney and Warner Bros.’ game companies and Electronic Arts Productions Inc., will continue.

The interim agreement secures wage improvements, protections around “exploitative uses” of artificial intelligence and safety precautions that account for the strain of physical performances, as well as vocal stress. The tiered budget agreement aims to make working with union talent more feasible for independent game developers or smaller-budget projects while also providing performers the protections under the interim agreement.

Duncan Crabtree-Ireland, SAG-AFTRA’s national executive director and chief negotiator, said in a statement that companies signing the agreements are “helping to preserve the human art, ingenuity and creativity that fuels interactive storytelling.”

“These agreements signal that the video game companies in the collective bargaining group do not represent the will of the larger video game industry,” Crabtree-Ireland continued. “The many companies that are happy to agree to our AI terms prove that these terms are not only reasonable, but feasible and sustainable for businesses.”

The union announced Wednesday that game development studio Lightspeed L.A. has agreed to produce current and future games, including the popular title “Last Sentinel,” under the union’s interim agreement, meaning it can also work with union talent as the strike persists.

© 2024 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed without permission.

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Video game performers reach agreement with 80 video games on AI terms (2024, September 6)
retrieved 6 September 2024
from https://techxplore.com/news/2024-09-video-game-agreement-games-ai.html

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