Hacker Newsnew | past | comments | ask | show | jobs | submit | jacksavage's commentslogin

Genuinely curious - what experiment can be used to verify the existence of time?


In engineering and sciences practice, existence of time is vitally accepted and measured.

We have experiments verifying not only existence of time but relativity of time is established strongly. There are couple of prominent topics supporting this view, links to peer-reviewed works.

1. Einstein's general relativity is first experimentally verified by Sir. Eddington https://en.wikipedia.org/wiki/Eddington_experiment The deviation is actually about time as well, interplay between geometry and gravity.

Subsequently for special relativity "Experimental Establishment of the Relativity of Time' https://journals.aps.org/pr/abstract/10.1103/PhysRev.42.400

This is actually what Carlo trying to explain in his YouTube interview.

Experimental Tests of General Relativity https://www.annualreviews.org/content/journals/10.1146/annur...

2. Existence of Biological clocks measuring time is understood by gene regulation and molecular setting:

Biological clocks https://www.pnas.org/doi/abs/10.1073/pnas.96.16.8819

3. Entropy production

On material systems. Evolution of time is tied to entropy production, for example using fluorescence spectroscopy

Measurement of Stochastic Entropy Production https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.97...

4. Relativistic effects on GPS.

Relativity of GPS measurement https://journals.aps.org/prd/abstract/10.1103/PhysRevD.68.06...

Satellite test of special relativity using the global positioning system https://journals.aps.org/pra/abstract/10.1103/PhysRevA.56.44...

These support's Carlo's explanations quite well.

5. Quantum Metrology

Even though causal ordering is not definite in quantum mechanics, once things measured they "collapse" to ordering.

Experimental aspects of indefinite causal order in quantum mechanics https://www.nature.com/articles/s42254-024-00739-8

Once things are measured, things should obey thermodynamics.

6. Atomic clocks and synchronisation, they are used to measure "time" in all sorts of scenarios.

The Measurement of Time: Time, Frequency and the Atomic Clock https://www.amazon.com/Measurement-Time-Claude-Audoin/dp/052...

7. Stellar navigation. Even though this sounds science-fiction, but it is indeed possible to measure time using pulsars.

Spacecraft Navigation and Timing Using X-ray Pulsars https://onlinelibrary.wiley.com/doi/abs/10.1002/j.2161-4296....


We need a Linux Subsystem for Windows


if only WSL existed ...


This CobraHead weeder has worked well for me

https://www.amazon.com/CobraHead-Original-Weeder-Cultivator-...


Let's say "A" has a direct dependency on "B". The author of "A" knows how they use "B" and are qualified to state what versions of "B" that "A" is compatible with. Yes, some assumptions are made about "B" respecting semver. It's imperfect but helpful. If I'm writing package/app "C" and I consume "A", I'm not qualified to decide what versions of "B" to use without studying the source code of "A". Some situations necessitate this, but it doesn't scale.

As a separate thought, it seems that it would be possible to statically analyze the usage of "B" in the source code of "A" and compare it to the public API for any version of "B" to determine API compatibility. This doesn't account for package incompatibility due to side effects that occur behind the API of "B", but it seems that it would get you pretty far. I assume this would be a solution for purely functional languages.


The Art of Electronics is an incredible resource. They have a companion book which guides you through hands-on labs. I have not read it, but I trust that it would be worthwhile.

https://learningtheartofelectronics.com/


Thank you - I recently picked up the art of electronics but wasn’t aware of this companion book.


I saw that the rendering library for echarts, zrender, is managed by a GitHub org associated with Baidu

https://github.com/ecomfe


This use case feels like it’s inching towards the world of the Black Mirror episode “The Entire History of You” where people are able to revisit and scrutinize any moment of their life no matter how trivial. It seems that overriding the memory related mechanisms in our brain would fundamentally change human social behavior. In some cases, such as for the purpose of introspection, perhaps this would yield excellent outcomes. For scrutinizing others, my intuition tells me that it will do more harm than good. This is the thought experiment posed by the episode.

I suppose similar discussions were probably held around the launch of google glass.


> We are not currently granting access to GPT-4-32K API at this time, but it will be made available at a later date.

https://help.openai.com/en/articles/7102672-how-can-i-access...


Thanks for the link.

The decision of burying these extra information in a support article, not cool!


I’ve used http://www.duckdns.org/ with a raspi for this purpose.


Recently, I had an exam through ProctorU and thought I'd try to reclaim some privacy using Windows Sandbox when I learned that they utilize TeamViewer to take full control of your computer. This was not allowed only because parts of the control panel were disabled and they couldn't verify that I had only one monitor. I used a mirror to show them my laptop and desk but that was not sufficient. Spent a lot of time that weekend just trying to take the open-book exam.

I really hope that universities will consider their students before adopting this type of software.


Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: