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isaacg

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I met Ellsberg when I attended a live recording of the podcast Philosophy Talk in 2019. It was called "The Doomsday Doctrine", it was about the policy of mutually assured distruction. I remember he talked about the difference between "their bomb is in the air, so we're launching" and "their bomb has exploded, we're launching". Politicians vacillate between the two, when history shows us that they are very, very different. Airplanes and bombers encourage the latter, while missile silos encourage the former. This makes missile silos a severe liability, as they encourage first-steike launches.

I remember talking to him briefly after the talk. It impressed me how decisive, opinionated, and well-thought-out he was, at his age.

He liked my T-shirt, which said "Statistics means never having to say you're certain."

I'm glad I got a chance to meet such an important and positive figure in US history.

Real qubits have flaws, and you could experiment to see under what conditions they work better or worse, like by applying magnetic fields. Simulated qubits are presumably flawless, and so you can't experiment with them.

Your reaction should be "astronomy fun fact, that will have no direct effects on anyone's life." This black hole is so dim and distant that it required a super powerful telescope to even notice it exists. It will have no effect on life on earth, except by adding to scientific understanding of the cosmos.

Moreover, black holes aren't death machines or anything. This black hole puts out much less light and energy than an equivalent-mass star. It's quite safe.

This object is rated as a 1 on the Torino scale, which combines probability of impact with size to get an overall danger level.

https://en.m.wikipedia.org/wiki/Torino_scale

The last time an asteroid reached a 1 on the Torino scale was late January. That asteroid is 2023 AJ1. It was downgraded to 0 on the scale in early February, after further observations decreased the estimated chance it will hit the earth.

Overall, objects reach a 1 on the Torino scale 3-4 times a year. No objects have reached level 2 or above since 2006.

Most cases of Polio are actually caused by vaccines - it's not a case of confusing cause and effect: https://en.wikipedia.org/wiki/Polio#Epidemiology

This is only the case because the vaccine has been so effective that the disease is close to being infected, and a vaccine-caused case is much less severe than a wild case, but they're still looking into a different vaccine type that will lower the risk of vaccine-caused infections.

Given that "The water ice was first chilled in liquid nitrogen to minus 320 degrees Fahrenheit" (77K), I think it would taste like frostbite.

The paper mentions that the new phase of ice reverts to something less interesting at 140K (-207F). Out of range for terrestrial experiences, which is why the article discusses finding it in space or on other planets.

The abstract of the underlying research paper: https://www.mdpi.com/1999-4923/14/11/2290/htm contains the quote "Vaccination prevented decreases on physiological measures (oxygen saturation, heart rate) and reduction in overall activity following FEN administration in male rats." These physiological measures are the precursors to overdose, which occurs when low oxygen saturation becomes hypoxia and becomes fatal.

To summarize, yes, this vaccine prevents overdose, as well as the other drug effects.

Queueing Theory 4 years ago

While an M/M/n is a good starting point, there are several extra important features to capture.

First, many of these applications have a load-balancing step, where arriving jobs are dispatched to queues at each of the machines. The performance will depend on how this load-balancing is done.

Second, some applications will parallelize across many cores or machine, while others will run each job on a single core or machine. This obviously has major implications for performance.

Third, your application may have variance in interarrival times or in job completion lengths. This is also important to measure and incorporate into a model. Something like Kingman's formula can be useful: https://en.wikipedia.org/wiki/Kingman%27s_formula

Queueing Theory 4 years ago

The only thing we use processing time for in the Nudge paper is to classify jobs as "Large", "Small" or "Other". If instead of exact processing times, we had estimates, the result would still work as long as a job that was estimated to large was typically longer than a job estimated to be small. So Nudge totally works in these more realistic settings.

If the estimates were super noisy, you might be better off using Nudge very sparingly, only when you're more confident about the relative sizes.

Queueing Theory 4 years ago

There's a transition zone from "fast" to "slow" fluctuations around the mean waiting time that's more complicated and is an area of active research. If the fluctuations are 5x below the mean waiting time, I'd guess the effects of fluctuation will be gone.

Here's a recent paper on the topic, if you're interested in the cutting edge research: http://www.cs.cmu.edu/afs/cs.cmu.edu/user/harchol/www/Papers...

Thanks, I'm glad to hear you liked the Nudge result!

Queueing Theory 4 years ago

Thanks for the question!

For thinking about bursty arrivals, a good rule of thumb is to look at the variance of the inter-arrival times. The key number is the variance of interarrival times divided by the mean interarrival time squared. The waiting time in a system with bursty arrivals will roughly be larger than the M/M/c by this multiplicative factor. Kingman's formula is the equivalent for the single-server setting: https://en.wikipedia.org/wiki/Kingman%27s_formula

For seasonality, if the arrival rates fluctuate over a long time period relative to the typical waiting time, it makes sense to just do separate calculations for the different conditions you experience. If the fluctuation is very fast, just use the average arrival rate.

For constrained queue lengths, there are a lot of theoretical results in this area, such as the M/M/c/c model: https://en.wikipedia.org/wiki/M/M/c_queue. The second "c" refers to the buffer size.

There is something to that - there's a concept called "Quantum Nonlocality", which says that an accurate description of an entangled quantum system must be nonlocal - to predict what will happen, we need to look at the whole system at once.

But nonlocality is different from the capacity for communication. To make accurate predictions about the measurements, one would need information from the earth and from mars. However, the results of the measurements cannot be used to transmit information.

These two concepts - what is necessary for prediction and what the results can accomplish - often line up in the classical world, but in the quantum world they are quite distinct. So your intuition has merit, but it reveals quantum nonlocality, not quantum superluminal communication.