Science News Thread (for articles that don't relate to ongoing discussions)

[darthgently]

4 minutes ago, magnemoe said:

Inverse square or rather cube x^3  affect any point source like a star, double the distance and its 6x dimmer. 10 times the distance and its 1000 times dimmer. 
Red shift is unrelated, think sounds of an train or ambulance passing you. Or you moving away from sound who it probably more of an bomber crew sound. 

Clear as mud.  I’ll need to ponder why Doppler would be any different.  Patience

[JoeSchmuckatelli]

2 hours ago, darthgently said:

Doppler would be any different

I think I see what you're getting at... But I could be wrong /confused too 

With the inverse sq decrease in brightness I see it as the ability to estimate your distance from the object at the time of measuring. 

With redshift, I think you're already guessing the distance (what it should be based on the above) and then the red/blue shift tells you whether the object is closing with you or retreating. 

I'm not certain, but distinction between the far off but stationary (w/r/to the observer) and a closer object retreating from the observer isn't difficult. 

[boriz]

3 hours ago, magnemoe said:

or rather cube x^3  affect any point source

I think x^3 relates to the volume, where as x^2 relates to the surface area. Also, I think redshift is a special case of the more general phenomena Doppler Shift. The 'red' meaning it relates specifically to light, where as Doppler Shift can be applied to light, sound, gravity waves, water waves, Mexican waves...

I think.

[boriz]

4 hours ago, magnemoe said:

Earth gravity is not uniform

Yes, you're right, Earths density is not uniform. I have corrected my question. Instead of "at the center of the Earth", it now reads "near the center of the Earth". Better to be precise where possible. Thanks.

[magnemoe]

3 hours ago, boriz said:

I think x^3 relates to the volume, where as x^2 relates to the surface area. Also, I think redshift is a special case of the more general phenomena Doppler Shift. The 'red' meaning it relates specifically to light, where as Doppler Shift can be applied to light, sound, gravity waves, water waves, Mexican waves...

I think.

My bad yes its X^2 as the power of point source at distance. 
And don't think its an major difference between redshift and doppler shift outside using red shift to estimate distance. 
Doppler shift of radar signals was used back in WW 2 to mask out static or slow moving target for air defense radars. 

[magnemoe]

7 hours ago, darthgently said:

Clear as mud.  I’ll need to ponder why Doppler would be any different.  Patience

In mud this one would use sonar. Khajiit think you sound Argonian. 

[darthgently]

Two amazing things in this video:

1. A camera with 1B fps that can capture light spreading through a room.

2.  The distance light travels in one nanosecond is pretty much one foot thus proving the value of the one true measurement system.

 

[magnemoe]

8 minutes ago, darthgently said:

Two amazing things in this video:

 

 

us proving the value of the one true measurement system.

 

3 GHz is 10 cm wavelength or why few stuff outside of chips works on the GHz range. 
Now that light speed is an major limit inside an box you can have on your desk is mindbogglingly in it self. 

[K^2]

15 hours ago, darthgently said:

I thought both gravity and EM followed the inverse square with distance.

Gravity doesn't. The relationship between the strength of gravity and distance is very close to inverse square if you're far enough from the Schwarzschild radius, but it's never exact. And yes, you can think of it as a symptom of non-linearity.

The easiest way to think about this is that photons have no electric charge. That means, two photons can't interact. Gravitational waves, however, do have energy, and therefore, gravitational mass. Gravity has gravity. So two gravitational waves do interact with each other. That means that if you do try to apply a particle description to gravity, gravitons self-interact in a rather nasty way, and that's related to problems of quantizing gravity.

There are limits that are easily addressable. As mentioned, gravity far way from anything like event horizon is really close to being linear, so linearized quantum gravity is a thing. Alternatively, if you want to study quantum effects in vicinity of very massive objects, but without directly impacting these masses, you can do mean field theory on quantum gravity, which is just General Relativity as it happens, and then you can do particle theory in curved space-time. Handy for cosmologists studying neutron stars, for example. The one place where we're absolutely out of luck is at the event horizon, where you simply cannot use either description.

 

5 hours ago, darthgently said:

The distance light travels in one nanosecond is pretty much one foot thus proving the value of the one true measurement system.

Light-nanoseconds really aren't a bad measurement unit. And that would make billionth's of speed of light a pretty good speed unit. Nano-c? maybe? It'd be pretty close to 1.5nc to 1mph. Pretty practical.

Edited December 27, 2024 by K^2

[JoeSchmuckatelli]

9 minutes ago, K^2 said:

It'd be pretty close to 1.5nc to 1mph. Pretty practical.

Whelp, you've done it.  

Now I have to Nerd-out my kids by telling them what fraction of C we're driving.

 

 

...Sadly, "I caaaaan't drive 36.66666667nc" doesn't fit into the song real well.

5 hours ago, darthgently said:

the one true measurement system

You sir, get my 'nod of the day'.

Freedom units!  

 

[darthgently]

6 hours ago, K^2 said:

gravity far way from anything like event horizon is really close to being linear

Is this one reason why Kepler’s 2-body eqns work well enough for KSP and such?  I imagine even Principia uses a linearized gravity then given the force levels involved

[darthgently]

Long, but interesting vid.  tl;dr: silicon dioxide based memory, as in memory in glass

https://youtu.be/tGCBBqtGrMQ?si=rzw_xfBTvP-3NJIt

[magnemoe]

On 12/27/2024 at 4:03 PM, darthgently said:

Is this one reason why Kepler’s 2-body eqns work well enough for KSP and such?  I imagine even Principia uses a linearized gravity then given the force levels involved

Newtonian gravity works well enough outside of Mercury and even there its just an accumulating error. 

KSP with just one gravity source adds more errors, most noticeable is that Jool might interact with an craft going to Duna or Dress if outside and distort the trajectory. Now for players this would looks like an bug unless its calculated into the trajectory preview. 

[darthgently]

5 hours ago, darthgently said:

Long, but interesting vid.  tl;dr: silicon dioxide based memory, as in memory in glass

https://youtu.be/tGCBBqtGrMQ?si=rzw_xfBTvP-3NJIt

After I watched that vid I kept thinking “glass memory”, then I remembered

 

[darthgently]

Asteroid tracking level-up

https://news.mit.edu/2024/mit-astronomers-find-smallest-asteroids-ever-detected-main-belt-1209

 

[darthgently]

Spherical honey

 

[boriz]

On 12/29/2024 at 12:14 AM, darthgently said:

Long, but interesting vid.  tl;dr: silicon dioxide based memory, as in memory in glass

https://youtu.be/tGCBBqtGrMQ?si=rzw_xfBTvP-3NJIt

That's James Tour's channel! A notorious[snip] scam artist who uses pseudoscience to [Snip] exploit the gullible and publish other peoples work under his own name. Can't trust word one from him. Wouldn't believe him if he said the sky is blue. Silicon dioxide based memory sounded interesting, until I saw the source. Now the idea is tainted just by association with him. Apologies to any actual scientists working on this, but I'd rather eat my own head than watch one second of anything on his channel.

Edited January 4 by James Kerman
Redacted by a moderator

[darthgently]

On 12/31/2024 at 7:20 PM, boriz said:

That's James Tour's channel! A notorious [snip] scam artist who uses pseudoscience to [snip] exploit the gullible and publish other peoples work under his own name. Can't trust word one from him. Wouldn't believe him if he said the sky is blue. Silicon dioxide based memory sounded interesting, until I saw the source. Now the idea is tainted just by association with him. Apologies to any actual scientists working on this, but I'd rather eat my own head than watch one second of anything on his channel.

I just looked at the data presented and don’t have a dog in this apparent fight.  [snip] I give some slack to the latter because no one can really know by way of science at this juncture and “I don’t know” is the only honest scientific answer.

 Personally, I’d find a universe that can self-assemble consciousness damn miraculous

Edited January 4 by James Kerman
Redacted by a moderator

[darthgently]

[Snip]

Ok, but what do you think about silicon dioxide as a digital memory element?

Edited January 4 by James Kerman
Redacted by a moderator

[boriz]

6 minutes ago, darthgently said:

what do you think about silicon dioxide as a digital memory element?

Personally, I'm in favor.

[JoeSchmuckatelli]

Ran across this and enjoyed it. 

 

Priest predicted Black Holes using Newtonian physics. 

https://www.bbc.com/future/article/20240626-the-priest-who-predicted-black-holes-in-1783

(edit - phone paste errors below) 

Also - I need to find out more about this church:

".Gilbert valued independence of thought, describing himself as "not attached to any body or denomination of men in the world". The family followed latitudinarian Christianity – a tradition that venerated reason over excessive doctrine and that had originated at the University of Cambridge under Isaac Newton" 

[kerbiloid]

8 hours ago, darthgently said:

Ok, but what do you think about silicon dioxide as a digital memory element?

It's great, but beware the water.

Spoiler

 

[darthgently]

 

[boriz]

That probe broke all previous speed records reaching over 430,000mph, approximately .064% of light speed.

Hail the probe!

[boriz]

On 1/1/2025 at 1:02 PM, darthgently said:

Having done some searching

I did some too. Try this: https://www.youtube.com/playlist?list=PLybg94GvOJ9HzCxBR9f4oi7MvfVcKAS6O (You might like '700 Papers and Still Clueless')

Sir Isaac Newton was a rare genius and should be on UK bank notes. [Snip]

Edited January 4 by James Kerman
Redacted by a moderator