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6 hours ago, Orwar said:

   Having better telescopes in the future doesn't change anything about how radio waves are dispersed in space, though.

   The point is, by the time radio waves leave our solar system, they're practically indistinguishable from the naturally occurring radio waves already in space. Thus, there won't be anything much for a far-distant civilizations to detect.

   "Shostak calculates that Nasa's recent broadcast of Beatles music towards Polaris, the North Star, using a 210ft antenna and 20kW of power, would require any potential aliens to have an antenna seven miles across to be aware of it. To actually receive it as music, this would need to be increased to a 500-mile wide antenna."

   Source: http://news.bbc.co.uk/1/hi/magazine/7544915.stm   

So you know that particles also come in the form of waves and you know what photons are right?

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14 minutes ago, Madelaine McMasters said:

Wave/particle duality has no effect on Orwar's signal-to-noise explanation, other than to set a floor on the noise level.

https://en.wikipedia.org/wiki/Quantum_noise

I read what Orwar wrote and I found it really interesting, especially that equation that I did not yet know and that I meticulously copied on a notebook that I always keep in my pocket for practical and useful things to use every day.
But I've never talked about noise and radio waves.
We certainly won't be able to see any stars in the sky if the photons decay.
I think that now that we have overcome this obstacle we can continue more easily in our gracious and nice chat, thank you.

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17 hours ago, Tama Suki said:

Everything my avatar does is projected into the cosmos as energy waves of interpretable data and one day some alien civilization will pick them up.

10 minutes ago, Tama Suki said:

But I've never talked about noise and radio waves.

Waves is waves.

Orwar's signal-to-noise ratio explanation covers the entire electromagnetic spectrum, from gamma rays to VLF (Very Low Frequency). The moment you said "interpretable", you established a requirement that cannot be met within our understanding of the laws of physics because of... noise.

What you think you say, what you actually say, what people hear, and what they understand you to mean, can be and often are different things.

18 minutes ago, Tama Suki said:

We certainly won't be able to see any stars in the sky if the photons decay.

Photon decay has never been observed. There is a theory that allows it, but the expected photon lifetime in our reference frame is 1018 years. The universe is currently 1010 years old.
https://physicsworld.com/a/what-is-the-lifetime-of-a-photon/

Cosmic expansion is the reason that distant stars will eventually vanish from our view.
https://www.forbes.com/sites/startswithabang/2018/08/17/the-universe-is-disappearing-and-theres-nothing-we-can-do-to-stop-it/?sh=574cbd2a560e

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10 minutes ago, Madelaine McMasters said:

Waves is waves.

Orwar's signal-to-noise ratio explanation covers the entire electromagnetic spectrum, from gamma rays to VLF (Very Low Frequency). The moment you said "interpretable", you established a requirement that cannot be met within our understanding of the laws of physics because of... noise.

What you think you say, what you actually say, what people hear, and what they understand you to mean, can be and often are different things.

Photon decay has never been observed. There is a theory that allows it, but the expected photon lifetime in our reference frame is 1018 years. The universe is currently 1010 years old.
https://physicsworld.com/a/what-is-the-lifetime-of-a-photon/

Cosmic expansion is the reason that distant stars will eventually vanish from our view.
https://www.forbes.com/sites/startswithabang/2018/08/17/the-universe-is-disappearing-and-theres-nothing-we-can-do-to-stop-it/?sh=574cbd2a560e

You forgot the gravitational wave part, even if it's a bit off topic. I understand that maybe adding links on links can be a tiring exercise, maybe next time. A more complete and exhaustive report would be welcome.
When redshift will be in a spectrum impossible to perceive with any instrument, perhaps, as Lawrence Krauss says, astrophysics will become a kind of philosophy because we will have no way of assuming that there is anything in the universe beyond our galaxy. I don't know when that will happen, perhaps in another 13.7 billion years. Maybe my post 13.7 billion years from now will make more sense to you, I'm a patient.

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1 minute ago, Tama Suki said:

You forgot the gravitational wave part, even if it's a bit off topic.

Signal-to-noise considerations are astronomically more challenging for gravitational waves.

8 minutes ago, Tama Suki said:

I don't know when that will happen, perhaps in another 13.7 billion years.

The timeline is here...
https://en.wikipedia.org/wiki/Future_of_an_expanding_universe

9 minutes ago, Tama Suki said:

Maybe my post 13.7 billion years from now will make more sense to you.

Implausible.

4 minutes ago, Tama Suki said:

I'm a patient.

Plausible.

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9 minutes ago, Krystina Ferraris said:

I knew it, this is all too familiar! 😂

I was too young and just as stupid as I am now to participate in the discussions but I really enjoyed reading it all 😄

It is not that difficult to do this.
Just prepare the links and put them on the table at the appropriate time.
I remember doing this a lot when I was doing ornithology and discussing birds with friends years ago.
I learned the names of many exotic species.
It is a fun and useful hobby as long as you are in the right context.

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22 minutes ago, Tama Suki said:

I remember doing this a lot when I was doing ornithology and discussing birds with friends years ago.
I learned the names of many exotic species.
It is a fun and useful hobby as long as you are in the right context.

ETA: On Saturday, we had a swift and steady 5°F breeze from the west, in excess of the minimum cruising speed for the hawks and falcons in my area. This affords them the ability to hover by flying into the wind. I imagine this is advantageous, as their visual systems needn't subtract away ground motion while searching for prey. It's fun to see them riding thermals over fields on calm days, but I love to see them take advantage of high winds.

Saturday felt unusual, though. On the short drive from my home to my emergency backup kid, I watched a total of six hawks hovering over road shoulders. This alone would be remarkable, but I also spotted two field mice scurrying across the road at other points on the trip. That's even more remarkable. Though I can't think of a reason a brutal cold wind would drive mice to risk road crossings, I do wonder if the hawks knew a good thing when they spotted it.

 

Edited by Madelaine McMasters
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5 hours ago, Madelaine McMasters said:

ETA: On Saturday, we had a swift and steady 5°F breeze from the west, in excess of the minimum cruising speed for the hawks and falcons in my area. This affords them the ability to hover by flying into the wind. I imagine this is advantageous, as their visual systems needn't subtract away ground motion while searching for prey. It's fun to see them riding thermals over fields on calm days, but I love to see them take advantage of high winds.

Saturday felt unusual, though. On the short drive from my home to my emergency backup kid, I watched a total of six hawks hovering over road shoulders. This alone would be remarkable, but I also spotted two field mice scurrying across the road at other points on the trip. That's even more remarkable. Though I can't think of a reason a brutal cold wind would drive mice to risk road crossings, I do wonder if the hawks knew a good thing when they spotted it.

 

 

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