@JohnRennie belated happy new year sir

Thanks, and a happy new year to you as well :-)

news.mit.edu/2021/kerstin-perez-dark-matter-0102

sir please have a look in the following link

There have been lots of experiments looking for dark matter particles, either directly or indirectly. So far all the experiments have failed.

sir has it been established that dark matter consists of particles at all?

This experiment is trying to detect the particles created when dark matter particles decay, so it would be an indirect detection.

@JackRod No, and in fact there has recently been renewed interest in the idea that dark matter might be black holes not particles. Give me a moment and I'll find the reference.

Here is a summary

This is the paper

But the truth is that right now we have no idea what dark matter is or even if it exists at all.

ok

that is a totally new thing

sir one more thing are u agreeing with machos theory

@JohnRennie

Again, no-one knows. I think there have been experiments to search for MACHOs using gravitational lensing, and those experiments failed to detect them.

Though this isn't an area I know a lot about.

arxiv.org/pdf/1702.08275.pdf

sir please have a go through this link once

@JohnRennie

That paper is basically the same idea as the link I posted above i.e. that dark matter could be black holes.

The problem is this is very hard to prove experimentally.

The current generation of gravitational wave detectors are not sensitive enough.

sir can u open page no 17 of this

According to the article I linked above the new James Webb telescope may be able to find evidence of the primordial black holes that could form dark matter.

OK, I'm on page 17 ...

there is figure no 11

on it

Yes

can we use this gravitational slingshot to travel alpha and other solar system?

I need to drop out for 5 mins. Back soon!

sure

I'm back!

NASA uses gravitational slingshots to send missions to the planets, but the amount of extra speed you can get from a gravitational slingshot is limited.

You couldn't use the slingshot method in the Solar System to get enough speed to get to another star, even a nearby one like Alpha Centauri.

@JohnRennie ok sir thanks for answering I believe still we have to long way for a unifying theory which relates everything

by the way how is ur health I read cases in UK are rising ?

Yes, sadly ...

Right now we have a huge wave of the new omicron variant of covid, but luckily it isn't causing any serious illness. A couple of people I know have caught it, and they said it was lie a heavy cold but no worse.

I have managed to avoid it so far :-)

How are things in your area?

it is increasing people now feel that they will not caught corona

so very few people wear masks

cases are rising since past one week

It was the same in the UK, though everyone is now wearing masks again because of the new variant.

everyday I open my pc some new study on corona comes some new claims

and stories

should I go back to home?

I guess the omicron variant will inevitably get to India, then you'll see a spike in cases again. But like I say it doesn't seem to be as serious as the original variant.

@JackRod I wouldn't be in any hurry to get home if you're at college.

It's much better for your studies to work at college as long as the college stays open.

sir I need ur help

And covid causes only a mild illness in young people. Have you been vaccinated?

seriously speaking I am not

If you aren't vaccinated they you should take reasonable precautions, but I wouldn't worry too much.

Can you get a vaccination at college? Maybe they have a vaccination centre? Or there is one nearby?

yes college is vaccinating

but I have some reserve

I know lots of people who have caught covid, some your age and some my age, and no-one I know was seriously ill.

actually, I always wear a double layer

mask I am not in a social circuit I am usually alone

that I love because it gives me time to work on my own activities

If the college is vaccinating then you should get vaccination as soon as you can. In the UK 40 million people have been vaccinated, so if there were any safety issues we would know about them by now!

yes sir

That's a big experiment - 40 million people! :-)

I feel but the problem is vaccine is no all-time saver immunity fade after some time then u have to go to booster dose

And I think the number of people who have received both vaccinations plus the booster - so three in all - is getting on for 20 million.

cycle will continue

in India it is 900million doubly vaccinated

Possibly, but if you have to get a booster once a year why is that an argument for not getting vaccinated?

I get a flu vaccination once a year as routine.

somewhere in my mind I believe natural immunity has overriding effect on XXXX

It's your choice, but in your place I would choose to get vaccinated ASAP. Well, I did choose to get vaccinated ASAP :-)

my problem is I have some allergic issues

so generally I avoid medicines

@JackRod You have to catch covid to get a natural immunity!

@JackRod I understand why you would be nervous, but the covid vaccine must be the best tested vaccine in the whole world and it has been proved safe.

ok sir ur talk gave me confidence and I will go to vaccination centre tommorrow

Excellent :-)

Let me know how it goes.

even my family members do not know that I am not vaccinated I told them I have been vaccinated

at college