Wednesday, 25 November 2015

GR100

All over the world people are celebrating 100 years of General Relativity (yes! Einstein proposed the theory 100 years ago and we have been using its applications ever since!) and Imperial was one of them. This Monday Imperial College held a lecture to celebrate this huge milestone. PhD students of Professor Hawking were speakers at the event and Stephen Hawking himself was meant to be there but unfortunately fell ill and was unable to come. Nonetheless, the talk went on with Hawking there in spirit.

Following on from this Imperial College wanted to find out what we (the public) thought would happen if we were sucked into a black hole. A cute Einstein badge was up for grabs and I just had to submit my thoughts so I could get one!

Here is my answer to the question which was, of course, aided with the knowledge I have gained so far in my physics degree at Imperial. Enjoy!



Before we answer the question what would happen if you were sucked into a black hole, let’s begin with the question what is a black hole?

Einstein has taught us that gravity can be considered as warped space-time. The denser an object the more warped space time is around the object. A black hole is an extreme case of warped space time - so extreme, that at the most warped part it is a singularity! A black hole is produced by an extremely heavy star that has run out of fuel and collapsed in on itself. 

A good analogy of this is if you consider a bowling ball on your mattress - the mattress would sink inwards and near the bowling bowl you would see more sinking. Now, imagine that the bowling ball didn’t change in size but changed in density and became really, really, REALLY dense, then, you’d see a lot of sinking in! if you had a marble it would sink straight into the hole but physics inside a black hole or near it is a little strange…

At the outer boundary of a black hole is the EVENT HORIZON - if you pass this point there is NO RETURN. The event horizon is full of streams of hot particles that radiate back into the Universe due to quantum effects, this radiation bears the name of it’s discoverer: Hawking radiation. Additionally, at this point the gravitational force precisely counteracts the light’s effort to escape the black hole.

So, now go back to the question of what will happen if you were to get sucked by a black hole?

Let’s consider a friend watching you far from the black hole - she/he sees you get ‘spaghettified’. The gravitational field strength at your feet is stronger than that at your head so you get stretched! You also appear to move in slow motion the closer you get to the event horizon. At the event horizon, your friend sees you ‘frozen in time’ and you stay there motionless and stretched until you get reduced to ash because of the Hawking radiation.

But what about if we consider it from your point of view what would happen? Nothing.. just nothing. No spaghettification (except if the black hole were small). This is because you are in free fall and so feel no gravity. You cannot escape the black hole as this would involve travelling backwards in time but time only goes forwards. 


All in all, getting sucked in by black hole is more entertaining for your friend that it is for you.



Within minutes after posting it on Twitter I received a tweet from @imperialspark informing me of my winnings! I was so happy - cannot wait to receive my badge (selfies will be posted here in due course). 

Why not send your thoughts on Twitter (@ImperialCollege) or Facebook (Imperial College London) and win a badge too!







Thursday, 19 November 2015

Popomatic safety sign complete!

After a long day of undergrad lab (Compton effect experiment where each reading takes half an hour!) I decided to take a break and start designing the safety sign for the popomatics (balloon-popping laser) I am building. I wanted to not defer too much from the original sign but add a modern twist to it.


The safety sign must include:



• Wavelength of the laser (532 nm - green laser)



• Type of laser (in this case CW which means Continuous Wave - basically, it has a continuous output and is not pulsed)



• Power of the laser (100 mW)



• Class of the laser (here, it is Class 3B which means you cannot look at the beam directly as it is hazardous to the eye but if you look at diffuse reflections for instance reflections from matte surfaces, preferably dark matte surfaces are not harmful - hence the need for the 'safety screens' I mentioned in the previous post here).



And also some safety statements about the permitted users and informing the user to not stare directly at the beam.





Here is the previous sign:


Original safety sign.



And here is the new one!

New laser safety sign for the popomatic!

Sunday, 15 November 2015

Popomatic update!

This week I've been busy sticking the 'safety screens' onto the lids of the popomatic (balloon popping laser). 

My orders, consisting of a clear silicone sealant and vulcanised fibre washers, arrived earlier this week and I could get to work on sticking the optical hardboards ('safety screens') onto the lids! (Half of the lids are still being delivered so I couldn't stick on half of the 'safety screens'). It was great to be back in the lab and to meet all the cool PhD students and postdocs again!

Here are a few videos and pictures of me sanding down the optical hardboards and applying the glue onto the pieces and sticking them on the lids! It's nice to see the popomatic slowly take shape!

Vulcanised fibre washers




Silicone sealant




The optical hardboards were glued onto the lids!

The finished lid put onto the popomatic! But I will need to add a safety sign onto this, which will cover the glue.


#PhysicsBanter




One of the most inspirational postdocs left on Friday and it was a little bit emotional. She had helped me so much in my first summer placement with the Plasma Group and she acted as my first ever female role model at Imperial College. She was the only female in the Plasma Group and I was totally inspired by her seamless knowledge, ability to work in such a male-dominated group and how she offered to help everyone that needed it. She is now going to work at SLAC and I am so happy for her! She is an amazing laser specialist and SLAC will certainly benefit from her presence! It's sad to see her go but she will be loved just as much at SLAC as we did at Imperial!

Here are a few images highlighting the stuff we did for her leaving do - it included some very tasty cake!

The AMAZING gift the Plasma Group gave her - a ruby rod used in laser experiments and she's a laser specialist - so right up her street!

Leaving lunch!

This was SCRUMPTIOUS!

Mmmmm....

The lovely Plasma Group! <3 

#PhysicsBanter

Laser thermometer #EndlessFun


An 'optical crowd'

Where gas jet experiments happen!

Friday, 6 November 2015

More updates on the popomatic!

Last week I received the optical hardboards (basically just really dense polystyrene sandwiched by card) which shall protect our eyes from the laser beam and shall be placed on both the top and bottom lids of the popomatics! The laser used shall be a class 3b laser that is hazardous for the eyes, thus, we must implement some safety measures.

I must admit, I did crack a few of the pieces of optical hardboard whilst I was cutting out the first pieces! Whoops - but I got there in the end! :)

In the following images you'll see me draw and cut out the pieces I need from the optical hardboard. A future blog post shall hopefully see me stick the pieces onto the lids!







Colouring pencils! Feels like I'm doing art coursework for school! ;)

Referring to my lab book for dimensions - that's why we need lab books!


The places where I needed to cut were drawn out...

...and cut out.




The left overs look a bit artistic!

The finished 'safety screens' and all the equipment I used - 'all in a day's work!' ;)






Friday, 23 October 2015

Summer Placement is not over

Yesterday I received an email from my summer placement supervisor which included great news - my plastic tubes for the popomatics arrived! I was over the moon! :) It was so exciting to hear that something that I designed using CAD software was coming to life! I couldn't wait to see the finished product, from computer screen to reality. So I went up to the Plasma Group and had lunch with the lovely people of Plasma. My supervisor was there and greeted me with Christmas has come early for you! He had left the tubes wrapped in their packaging just waiting for me to unravel them. I couldn't contain my excitement. After lunch, I went down to the lab and got to work on unwrapping the packaging from all the plastic pieces.

It was so lovely to be back in the lab and it felt like I hadn't left. Once unwrapped the plastic pieces were SO SHINY! It certainly felt like Christmas.

Here are some pictures and a video of what I was up to this afternoon:


I'm coming home ;)

Woo! The plastic casings arrived! 

The lid


This is where the balloon that shall be popped by the laser will fit through before being pumped with air

Screw holes ready for the aluminium rail to be fitted


The lids

The lid fitted onto central column


The casings all unwrapped

After this I had tea with the new PhD students - it was great to see them again and have some #PhysicsBanter 

My first ever magazine article!

I am so excited to announce that my first ever magazine article has been published and is available to read here, in Catalyst Magazine. 

It is an article about magnetic confinement fusion and the work of Tokamak Energy, a private UK company. Tokamak Energy aims to develop fusion energy faster using smaller machines and new technologies. Although this article is aimed for secondary school students please feel free to read and learn more about fusion!

I owe my huge thanks to Dr. Melanie Windridge and Tokamak Energy for giving me the incredible opportunity to work with them at the Royal Society Summer Science Exhibition 2015 where I was able to meet David Sang, the chief physics editor of Catalyst Magazine. From here I was able to write an article for the magazine with the aid of Tokamak Energy and Dr. Windridge. It was great fun and the end result is better than I'd ever imagined! Hope you enjoy it!

At the Royal Society Summer Science Exhibition (2015) with Tokamak Energy


Wednesday, 21 October 2015

Careers Evening at my old school

Just as I was going to my lab session at university on Monday I had a quick read of my emails and found that the Careers Evening I signed up to do at my old school was tomorrow! Luckily I didn't need to prepare a presentation though otherwise I think I might have fainted! ;)

I was going to have a stand in one of the rooms of the main building of the school where a school friend of mine and myself would talk to the students (Yr10-13) about university life, A level choices, UCAS, but also share experiences of the subject we were studying, physics in my case.

So tomorrow came along (yesterday at the time of writing) and I arrived at school welcomed by the sixth form students - some of which I had helped them with their personal statements. I was given a visitors badge and went into the room that I would be in for the rest of the evening. I found that my physics teacher had left the plasma ball and the leaflets I made as well as some IOP (Institute of Physics) ones outside the room - so lovely! (Thanks Sir!) I then began setting up and the final touch was switching the plasma ball on. My old school friend was also in the room with me and he loved the plasma ball as much as I did even though he's a biochemist! ;) We went to get a few refreshments before the clock struck five. We were back in our positions and the students and parents began to come in. By six, they were flooding in!

A lot of the students had recognised me from the school newsletter from 2013! It was so nice that the students could relate to me because I used to wear the same uniform, sit in the same classroom seats and had the same teachers. For the GCSE students I spoke about A level choices which was the next biggest chapter in their lives and told them that they shouldn't rule out physics because everyone complains that it's hard or its a guy subject. I spoke about the numerous career opportunities that could await them if they chose physics and that they would stand out from many others if they had it as one of their A level choices.

To the A level students I spoke about the UCAS process, personal statement writing and how to research different university courses so that they could choose the perfect one for them. I also gave them tips on finding work experience and to the lovers of STEM I encouraged them to apply to some Exscitec courses - which I loved when I applied!

I honestly came home with such a huge smile on my face! Some of the students I saw I had mentored a few years ago and now they've grown so much! It was lovely to be a part of the school again for an evening and inspire the younger generation.

I would definitely recommend going back into your old school for a talk, careers event or any other activity and share your experience. The students will certainly appreciate it and you'd be a huge inspiration for them too!

Here are some pictures from the Careers Evening:

I am reunited with the plasma ball!

My stand