Saturday, 30 September 2017

Event horizons of approaching black holes

I think that the event horizons of approaching black holes should repel as they approach.

I was intrigued when I posted a comment on PBS space times' YouTube video and the response was "do the math".

It took me a while but now at least I have something to point at, and I think it was worth the effort given my lack of background in (astro)physics.

The source code is available in SourceForge for you to try out yourself.
I'm on Debian so you'll need make and g++/clang++, I tried to keep it as simple as possible.
The program generates an ".off" file which describes a point cloud.

The image above is what you get when you load the file into MeshLab and take a snapshot.
This was generated by:
./event-horizon  --d=1.6 --res=1e-4
 You can try other values by varying the parameters, the code isn't that complicated to understand.


Update 2017-10-03

I wrote a CGAL variant that generates full surfaces but as it turns out one sometimes gets its normals inverted - it looks kinda cool though!

Update 2017-10-03 part 2

After several hours mulling it over, I figured out how to write a libigl version with the NanoGUI.
With this version one can look around the model and directly modify viewing attributes as well as the distance (d) parameter.

These screenshots were taken from running
./event-horizon-igl -d 1.382012173 

The thing to note is the blob hiding in the middle of the combined event horizons - it's outside the event horizon but isolated from the rest of space-time.

It's also shrinking as the singularities approach one another.

I'm guessing its entropy is decreasing too, so time is going backwards.

It may or may not be being bombarded with leaking firewall from the two black holes.

Finally, it's becoming so small and so close to the event horizons that millions or billions of years will pass for it while for us it would be just a moment.

Sounds like a pocket universe to me, a time-reversed big bang!

Update 2017-10-13

It looks like the singularities meet inside that pocket of regular space-time!
I used the radii corrosponding to the 29 and 36 solar mass black holes whose gravity waves were detected.

If you run
./event-horizon --r1=.855484 --r2=1.06198 -d 5e-13 --res=1e-11
 here's a very zoomed-in view of what you get (the dot in the middle is the origin)

I wasn't expecting that!

Thursday, 21 July 2016

Quantum Gravity

The double slit experiment

Just read the Wikipedia article which explains four possible explanations for this phenomena.

Here's my take on it.

The exact location of quantum particles such as electrons, photons atoms... is a probability distribution explained by Heisenbergs uncertainty principle - a bell curve.

Quantum tunneling is the phenomena where particles can appear on the other side of a barrier without having sufficient energy to do so.

It also demonstrates that the uncertainty principal isn't just an idea, it explains phenomena observable in nature.

By the conservation of mass-energy particles such as electrons and atoms aren't cancelling themselves out due to interference as this would release a lot of energy.

If electrons aren't canceling themselves out and their hitting the detector in bright and dark bands then their probability distribution function is being affected by the slits.

They either hit the slit mask where they are absorbed or reflected or travel through it.

Quantum tunneling even allows them to reach the other side of the slits by traveling some non-zero distance inside the slit mask that classical physics would prohibit.

Somewhere in this journey from one side of the slit mask to the other the probability distribution of the particles is affected making their final trajectory different to that of a particle traveling in a straight line without the double slit barrier.

If these particles have mass then it's at the quantum level.
If some thing's changing the direction of such a particle and it's not one of the other atomic forces then were left with one conclusion - quantum gravity.

Friday, 10 April 2015

Hyper Revo 26 Inch Dual Suspension Mountain Bike - Men's - White

I bought this bike from Argos's ebay Ireland web store - here it is.
Curiously, the Argos Ireland web site didn't offer home delivery at the time - maybe it's changed since then.

Anyway here it is out of the box.

45 minutes later and I had it assembled as the first picture shows.
Incidentally don't lie it down that way up - turn it over so the pedals are on top, it makes it a bit easier to assemble that way.

It actually ended up being taller than my old touring bike once I'd adjusted the seat so my legs would stretch to their full extent, so I need to kick my leg up a bit higher or just make use of the lack of a cross bar and mount it that way.

I found the seat would move around when I did my first ride - use a proper torque wrench to keep it from doing this.

The snap lock on the seat works well but you have to remember how it was mounted when you put it back on otherwise you'll be adjusting it back to the way it was after cycling 20 meters, which is a bit annoying.

As far as gears go, since I'm used to touring bikes I just keep it at the highest pedal gear (operated by the left hand gear adjustment) and just use the wheel gear, numbered 1-6, with the right hand.

Sometimes going up or down a gear doesn't have an effect - then you need to go one past and back up, but there's not a big difference between one gear and the next, so that's no big deal.

You'll need a proper two-hand floor pump to fill the tires.

The wishbone suspension was a bit too spongy the way it was set so I tightened it about another 20% to stiffen it up.

I bought some mud guards and a bag holder for it but when the bag holder is weighed down it hits the mud guard which hits the tyre - a problem with dual suspension bikes.

You'll need ones that specifically mention "for dual suspension bikes" otherwise you'll be disappointed.

I got mine from Lidl, and ended up putting on the bag carrier using the supplied tools in the shop, so I could leave with my shopping inside the box the bag carrier came in, on the bag carrier.

It took about 20 minutes to attach.

I guess you dirt bike enthusiasts will be yelling at the screen - "you don't have mudguards or a bag holder when you're dirt bike racing", and yeah, you're right.

I was just looking for a bike that would do what I want and would last, and this certainly looks like it'll do that - and a bargain.

The bag holder was probably a waste of money - I'll use a back pack for heavy shopping in future.

I haven't ridden in the rain or through mud so I don't know how good the mudguards are, so I'll update this post when I do.

It certainly is a smooth ride, and those bumps and holes in the road are a lot less jarring to cycle over than they were before.

It has a steel frame so it weighs some, but it cruises like a Mercedes Benz, or at least how I imagine one would.

Happy trails!

Sunday, 18 May 2014

Walking is a kind of dancing

People worry about robots stealing jobs.

Let me explain why this is hilarious.

We are expressions of our genes, which are an expression of our environment.

The genes of the beings around us affect our environment too, but because they are also expressions of the environment, it's all about the environment.

Robots interact with their environment through programs - software running on hardware.

In a very real sense we are programs running on our genes - particular permutations of all possible expressions.

We are to genes as a dance is to us.

Epiphany is to revelation as we are to the idea of us.

Friday, 4 April 2014


I gave up trying to think of  a title for the segment of the "Pineapple Express" movie on Netflix that most illuminated what corruption really means.

Drug Dealer: what do you do?
Process server: I work for a company that serves legal documents. Sometimes I go in disguise to get them to admit to who they really are so I can serve them the documents.

I haven't seen the rest of the video yet, I hope it's fun.

OK so you're wondering "the dude takes drugs, what's the diff?
He shows up and puts on a disguise and hands some papers over.
Clowns do most of that."

The issue: what if the company the server works for has a connection to the drug dealer?

"Hey, hang around, I've got a new thing" - that could be useful.

Like I said, I'm watching it now on Netflix, so if this turns out to be a key point to a plot twist, then oops!

Tuesday, 1 April 2014

pandoras promise

I thought I'd take a break from watching "Pandoras promise" - a documentary about how nuclear power is maturing to become the safe affordable source of energy the world needs - I know I (was) a cynic too.

I thought I'd google it for more information - I found the site.

It turns out there are several ways to watch it - long story short, it's a commercial production and fees are involved if you want to see it.

Maybe it's just me, but if the nuclear power industry wanted to improve their reputation, they'd fund an independent body to make a "living video" - one that was continually updated - even once a month, to present an independent understanding of the costs and benefits of nuclear power.

I for one was shocked to discover that the background radiation levels in Brazil are more than 30 times those in Chernobyl.

Then there's "coal kills more people by about 10000:1 or greater than radiation", if I read the statistics right.

Come to think of it, there's another industry that feeds on fear and uncertainty - the distribution of wealth, that drugs regulation kills children
so I think that big commercial interests actively encourage this sort of thing.

Sunday, 30 March 2014

The Treatment (SuperValue Raheny)

I put this in a seperate post to the previous one so that it could be referenced and commented upon by itself.

It struck me just last night (28 March 2014) that I get "the treatment" at my local SuperValue in Raheny and only notice it by its absence.

The treatment

Let me walk you through the steps

the introduction

A female member of staff walks up behind me, puts an empty cardboard box on the counter (the queue for the off-license section is along the counter) and starts tearing it up, getting my attention with the noise. She looked like Maggie Grace.

the rescue

The guy behind the counter - the one serving me, stops what he's doing, turns to her and asks her if she's "OK".

the reinforcement

A member of security walks straight at me, stops three feet away and continues "protecting the public and staff" until I complete my purchase and leave.

In summary

If I weren't such a regular patron of my local SuperValue I'd ask for the manager and let the chips fall where they may, but that might be construed as causing a fuss, and who among us likes a fuss?

I wonder if it's because I have a pony tail, but of course one of the key aspects of any unwritten policy is to not admit it.

A key aspect of any "treatment" is that each part, on it's own, looks reasonable, it's usually only the recipient of the treatment that knows they're being singled out.

It's easy for on-lookers to assume that the recipient somehow deserves it or that they missed something.

Maybe they're using me for practice.

Maybe I've got one of those faces.

Discrimination, or someone "fitting my description" caused a fuss before, what's the difference?