Welcome to DU! The truly grassroots left-of-center political community where regular people, not algorithms, drive the discussions and set the standards. Join the community: Create a free account Support DU (and get rid of ads!): Become a Star Member Latest Breaking News Editorials & Other Articles General Discussion The DU Lounge All Forums Issue Forums Culture Forums Alliance Forums Region Forums Support Forums Help & Search

CloudWatcher

CloudWatcher's Journal
CloudWatcher's Journal
January 15, 2024

Black holes don't have singularities!

For the black hole fans that wonder about all those singularities punching holes into other dimensions ... a giant in the field has declared that singularities don't actually exist.

The giant? Roy Kerr whose solution to Einstein's equations predicted spinning black holes before they were discovered.

He released this (free to download) paper in November: Do Black Holes have Singularities?

An enjoyable popular press summary of it: “Singularities don’t exist,” claims black hole pioneer Roy Kerr

And there's a YouTube review by Anton Petrov:



Btw the paper includes a little snark:

The author has no doubt, and never did, that when Relativity and Quantum Mechanics are melded it will be shown that there are no singularities anywhere. When theory predicts singularities, the theory is wrong!


I hope others find this as interesting as I do! Belief in singularities has been a pet peeve of mine for a long time.
December 28, 2023

And a few seconds after 31 minutes after noon ....

It will be 12/31/23 12:31:23

October 4, 2023

Cats are perfect

From Scientific American, so you know it's ... well, at least worth reading

Cats Are Perfect. An Evolutionary Biologist Explains Why

Anjali Goswami thinks cats are perfect—not in the same way that the average cat person might admire their beauty, athleticism and independence of spirit but from a scientific standpoint. Goswami is an evolutionary biologist at the Natural History Museum in London who studies large-scale patterns of evolution in vertebrate animals through time. She contends that cats—from tabbies to tigers—are quintessential products of evolution. I sat down with her to find out why. Her explanation reveals cats, and the meaning of evolutionary success, in a fascinating new light.
September 23, 2023

1000 houses

I'm expecting about 1000 houses to spring up when he dies. The results of just a little detour on his journey.

September 7, 2023

We're blocking twitter at our house

I'm the "admin" for our home network. I've finally had enough and added twitter to our Raspberry-PiHole black-list.

We're blocking all of twitter.com, x.com, and t.co now.

I suggest everyone do the same with their ad blockers or router firewalls or whatever it takes.

And I'm posting here to encourage people not to post links into the twitter, we won't be able to see them

November 5, 2022

Quantum Winter

Sabine Hossenfelder does a great job explaining why there is way too much hype about Quantum Computing research and predicts a "Quantum Winter" when the sponsors figure out they've been taken for a ride. I'm glad to see I'm not the only one that has been rolling their eyes at every ridiculous news story about the coming future of Quantum Computing and Quantum Internet. But beware of her deadpan humor and try not to be drinking your coffee when watching

July 6, 2022

Post-Quantum Encryption

I've been worried if our dependence on public-key encryption was going to be a serious problem when quantum computing eventually becomes real and widely available. But it looks like the encryption experts have been busy and are working to duck this bullet. This is excellent news, I hope it stands up to review.

From NIST:

NIST Announces First Four Quantum-Resistant Cryptographic Algorithms

Federal agency reveals the first group of winners from its six-year competition.

GAITHERSBURG, Md. — The U.S. Department of Commerce’s National Institute of Standards and Technology (NIST) has chosen the first group of encryption tools that are designed to withstand the assault of a future quantum computer, which could potentially crack the security used to protect privacy in the digital systems we rely on every day — such as online banking and email software. The four selected encryption algorithms will become part of NIST’s post-quantum cryptographic standard, expected to be finalized in about two years.
...
The announcement follows a six-year effort managed by NIST, which in 2016 called upon the world’s cryptographers to devise and then vet encryption methods that could resist an attack from a future quantum computer that is more powerful than the comparatively limited machines available today. The selection constitutes the beginning of the finale of the agency’s post-quantum cryptography standardization project.


... but of course there is a lot of work to do before our public key encryption infrastructure is worthless.

From CERT

Prepare for a New Cryptographic Standard to Protect Against Future Quantum-Based Threats

Although NIST will not publish the new post-quantum cryptographic standard for use by commercial products until 2024, CISA and NIST strongly recommend organizations start preparing for the transition now by following the Post-Quantum Cryptography Roadmap, which includes: ... [see original article for a long list of useful hints about how to transition to the new encryption algorithms]

For additional guidance and background, CISA and NIST strongly encourage users and administrators to review:


In the meantime, everyone should realize that the encrypted files (and possibly archived https sessions) being made today will not withstand decryption attacks once quantum computing becomes cheap and widespread.
June 25, 2022

US Passport Fees

We should be lobbying to eliminate passport fees. Far too many people in the US have no idea how the rest of the world works and think that how we do things here must be the best way.

And ... soon we might need to leave the country to get health care.

Map from Center for Reproductive Rights: The World's Abortion Laws

International travel should be encouraged and even subsidized. Not just limited to those that can pay extra fees to prove citizenship.

May 29, 2022

How you can sponsor Ukrainian Refugees to come to the US

If you have the resources to financially support your Ukrainian refugee friends, it's possible to get them here quickly!

First hand experience: a Ukrainian friend and I just went through this process. It took us one week to get full approval. And most of that time was my gathering documents to prove my financial state. And it helped that I had copies of docs handy to prove my citizenship.

Perhaps we just got lucky, but fyi it's possible. It was free. It was all online (for us) and it was fast. I'm still stunned. Some of the other processes have estimated times of many months. And they gave no hints about how long this process might take.

NY Times Story (4/25) on the program: https://www.nytimes.com/2022/04/25/us/politics/americans-sponsor-ukrainians.html

The Biden administration on Monday established a program that allows Americans to sponsor Ukrainian refugees and have them temporarily stay in the United States under a system known as humanitarian parole.

The program, called Uniting for Ukraine, is a piece of a larger initiative to temporarily resettle as many as 100,000 Ukrainian refugees, but migrants themselves cannot directly apply. Instead, a sponsor in the United States must apply on their behalf, and then migrants may complete the process after their sponsor is approved


Profile Information

Name: Jim
Gender: Male
Hometown: Frostbitefalls
Member since: Mon Apr 2, 2018, 08:44 PM
Number of posts: 1,869
Latest Discussions»CloudWatcher's Journal