Jul 272017
 

There is a brand new video on YouTube today, explaining the concept of the Solar Gravitational Telescope concept:

It really is very well done. Based in part on our paper with Slava Turyshev, it coherently explains how this concept would work and what the challenges are. Thank you, Jimiticus.

But the biggest challenge… this would be truly a generational effort. I am 54 this year. Assuming the project is greenlighted today and the spacecraft is ready for launch in ten years’ time… the earliest for useful data to be collected would be more than 40 years from now, when, unless I am exceptionally lucky with my health, I am either long dead already, or senile in my mid-90s.

 Posted by at 11:27 pm
Jul 162017
 

Thirty years ago today, I stepped off an airplane at Montreal’s Mirabel Airport and presented my immigration papers to a Canadian border protection official. Some half an hour later, I formally entered Canada as a freshly minted landed immigrant.

I almost forgot that today is that anniversary. When I suddenly remembered and mentioned it to my wife, she suggested that we have some chestnut puree (a popular delicacy for many Hungarians) after dinner. She then presented me with a bowl:

Yup, that’s the number “30” in whipped cream.

 Posted by at 11:12 pm
Jul 142017
 

An old friend showed up on our doorstep a short while ago, just as I was getting ready to call it a day:

This is MJ the cat. He has been visiting us for more than 12 years already, but tonight was his first visit in 2017.

We know where he lives, and we have seen him in recent weeks, so we knew he was okay. But he is getting a bit old. So we were not surprised that he wouldn’t come this far (his home is several hundred meters from here, across Cobourg street, which is not free of traffic even late at night.) But lo and behold, tonight we noticed him peeking through the vertical window pane next to our front door.

He stayed for a while. He gobbled down some cat food so vehemently, it’s as though he has been starving. (For the record, we know that he is treated well by his owner.) He even got some cat treats and a little bit of catnip. Then finally, once he had enough of our company, he just turned around and left.

Good old MJ. I hope he will keep coming back for many more years to come.

 Posted by at 2:17 am
Jul 132017
 

Slava Turyshev and I just published a paper in Physical Review. It is a lengthy, quite technical paper about the wave-theoretical treatment of the solar gravitational telescope.

What, you say?

Well, simple: using the Sun as a gravitational telescope to image distant objects. Like other stars, the Sun bends light, too. Measuring this bending of light was, in fact, the crucial test carried out by Eddington during the 1919 solar eclipse, validating the predictions of general relativity and elevating Albert Einstein to the status of international science superstar.

The gravitational bending of light is very weak. Two rays, passing on opposite sides of the Sun, are bent very little. So little in fact, it takes some 550 astronomical units (AU; the distance between the Earth and the Sun) for the two rays to meet. But where they do, interesting things happen.

If you were floating in space at that distance, and there was a distant planet on the exact opposite side of the Sun, light from a relatively small section of that planet would form a so-called Einstein ring around the Sun. The light amplification would be tremendous; a factor of tens of billions, if not more.

But you have to be located very precisely at the right spot to image a particular spot on the exoplanet. How precisely? Well, that’s what we set out to figure out, based in part on the existing literature on the subject. (Short answer: it’s measured in tens of centimeters or less.)

In principle, a spacecraft at this distance, moving slowly in lateral directions to scan the image plane (which is several kilometers across), can obtain a detailed map of a distant planet. It is possible, in principle, to obtain a megapixel resolution image of a planet dozens of light years from here, though image reconstruction would be a task of considerable complexity, due in part to the fact that an exoplanet is a moving, changing target with variable illumination and possibly cloud cover.

Mind you, getting to 550 AU is costly. Our most distant spacecraft to date, Voyager 1, is just under 140 AU from the Sun, and it took that spacecraft 40 years to get there. That said, it is a feasible mission concept, but we must be very certain that we understand the physics thoroughly.

This is where our paper comes in: an attempt to derive detailed results about how light waves pass on both sides of the Sun and recombine along the focal line.

The bulk of the work in this paper is Slava’s, but I was proud to help. Part of my contribution was to provide a visualization of the qualitative behavior of the wavefront (described by a hypergeometric function):

In this image, a light wave, initially a plane wave, travels from left to right and it is deflected by a gravitational source at the center. If you squint just a little, you can actually see a concentric circular pattern overlaid on top of the distorted wavefront. The deflection of the wavefront and this spherical wave perturbation are both well described by an approximation. However, that approximation breaks down specifically in the region of interest, namely the focal line:

The top left of these plots show the approximation of the deflected wavefront; the top right, the (near) circular perturbation. Notice how both appear to diverge along the focal line: the half line between the center of the image and the right-hand side. The bottom right plot shows the combination of the two approximations; it is similar to the full solution, but not identical. The difference between the full solution and this approximation is shown in the bottom left plot.

I also helped with working out evil-looking things like a series approximation of the confluent hypergeometric function using so-called Pochhammer symbols and Stirling numbers. It was fun!

To make a long story short, although it involved some frustratingly long hours at a time when I was already incredibly busy, it was fun, educational, and rewarding, as we gave birth to a 39-page monster (43 pages on the arXiv) with over 300 equations. Hopefully just one of many contributions that, eventually (dare I hope that it will happen within my lifetime?) may result in a mission that will provide us with a detailed image of a distant, life-bearing cousin of the Earth.

 Posted by at 10:56 pm
Jul 122017
 

Microsoft broke my Skype device, and I hate them for it.

It’s one of these:

Yes, it’s an older gizmo. About ten years old. I even had to repair it once, replacing the small condenser microphone in the headset, which went dead.

But we really liked it. It worked very well. It is a dual-line phone: landline + Skype. And while it has no video, chats, teenage chatbots and such nonsense, it performs the basic function of Skype flawlessly: It lets you make bleeping voice calls.

Or rather, it used to perform that basic function flawlessly. Today, the device signed itself out of Skype forever, it appears, if online news sources about the demise of Skype devices can be believed.

Damn you, Microsoft. If this is how you are “improving the user experience”, please stuff your improvements where the Sun doesn’t shine. I don’t want smileys. I don’t want chatbots. I want good old, solid, reliable Skype that, among other things, lets my wife and I call our aging parents overseas, lets me talk to clients, and lets me talk to colleagues. And, well, just plain works.

Sure, we can use Skype on our smartphones. And we do, when the occasion warrants it. But this device was convenient, too. And I really cannot understand why support for it had to be killed by Microsoft. Perhaps pure spite?

One of these days, I’ll start compiling a list titled, How can you tell that a company hates its customers? If I ever get around to doing it, this thing with Skype will certainly make that list.

 Posted by at 5:55 pm
Jun 212017
 

I just finished watching a 2016 Hungarian documentary film about the early days of the computer game industry in Hungary.

I was also interviewed via Skype for this film, albeit not much of my conversation with the filmmaker remained in the final cut. But that’s okay… it is, in a sense, fitting, because after the first few “heroic” years, I was no longer taking part in games development, whereas others continued and produced some amazing software.

Anyhow, I enjoyed this film. I met familiar faces (though I admit I would not have recognized all of them on the street after 30-odd years) but I also found out details about those days that I just didn’t know. I don’t necessarily agree with everything that was said in the film, but by and large, I think it paints an interesting, reasonably complete, accurate and balanced picture of what computer game development was like, what it meant to us in the early 1980s behind the Iron Curtain.

For what it’s worth, I bought my downloadable copy. (No DRM.) I think films like these deserve our support.

 Posted by at 5:35 pm
May 312017
 

I am watching the morning news and it’s all about numbers. Some good, some not so good, some really bad. Here are a few, in descending order:

  • 2018: The year when Ottawa plans to introduce a new low-income transit fare.
  • 417: The provincial highway number of the Queensway, which has been reopened after yesterday’s huge crash.
  • 175.6: The amount of rain, in mm, that Ottawa received in the month of May.
  • 80: The estimated number killed by a massive ISIS terrorist bomb in Kabul.
  • 21: The highest expected temperature of the day and, incidentally, the entire week, in Centigrade.
  • 15: The new minimum wage, in Canadian dollars, as proposed by the Ontario provincial government.
  • 7: The age of a baby, in months, who died allegedly due to her mother’s negligence in Gatineau.

I thought of turning these bullet points into a numbered list, but that would have been too confusing.

 Posted by at 8:25 am
May 292017
 

Is your mother proud of you being a crook?

I have asked this question many times in recent months; basically, every time I receive a call from the “computer support department”, trying to tell me how my computer is full of viruses or whatever.

I usually don’t expect an answer; as a matter of fact, I usually just hang up, although more often than not, the other party hangs up first before I get a chance. Understandable… that’s what they are trained to do by their criminal masters.

Today, for some reason, I chose not to hang up. And the gentleman on the other and of the line asked me to repeat myself instead of hanging up on me. I obliged. After a moment of silence, I actually got an answer.

“Well, sir, I need the money.”

That was an unexpectedly candid admission, not that I was not aware of this basic truth. These callers, usually in boiler rooms somewhere in India or Pakistan, do this because they need to earn a living.

But it’s one thing to earn a living, it’s another to defraud vulnerable people, old ladies and whatnot. I told that much to this agent. He just repeated himself, defensively: “But I need the money.”

So I told him that I understand. That I, too, was a refugee once 30 years ago. (True.) But even when I had no money, I did not start defrauding people. I asked him to think about this, please; then thanked him and hung up.

Did I accomplish anything? I don’t know. Is it valid to compare my situation 30 years ago: granted, a refugee, but a refugee in a first world country (Austria) with no family to worry about and with guaranteed shelter and food at the Traiskirchen refugee camp, which I declined to take advantage of only because I found work (no fraud involved, but it’s true that I had no work permit) and I was able to afford better accommodations?

Yes, I read Les Misérables. No, I do not want the poor to be disproportionately punished, with no grace or mercy.

Still, I think there is an ethical line to be drawn here. No matter how great your need is, I still don’t think this moral justification applies when you work for a criminal enterprise, earning a living from defrauding vulnerable people halfway around the world.

 Posted by at 2:21 pm
May 182017
 

I am no photo artist, and my best camera is, well, my phone. That’s it.

Even so, a few minutes ago I felt compelled to take a couple of photographs. We are a few minutes away from sunset and a big storm just began. Then I looked out my window and I found the building across the street brighter than the sky above.

The light came from the other side of the sky. The Sun was not visible but the sky in that direction was bright enough to light things up.

Photographs (especially, photographs taken with a phone) really don’t do these sights justice. The contrasts were amazing.

 Posted by at 8:29 pm
May 082017
 

Not only is there severe flooding in our region (I’ve lived in Ottawa for nearly 30 years, and I’ve never seen anything remotely like this) but this “spring” weather is anything but.

In fact, yesterday CTV News almost apologized for their forecast:

And the saddest part? They were not wrong. I see flurries outside.

Fortunately, the flooding doesn’t affect us, despite our proximity to the Rideau River.

 Posted by at 11:57 am
Apr 182017
 

I sometimes take pictures of our cats.

Very rarely, the pictures are actually interesting. (I am no photo artist.)

This morning, I snapped a picture of our cats Kifli and Rufus, as they found a place on top of some Amazon shipping boxes.

What I didn’t expect is the effect of light, filtered through the blinds, on their fur, especially Rufus’s.

 Posted by at 6:56 pm
Apr 082017
 

Remember what radio used to be like, especially shortwave?

Many stations had an interval signal. This signal, usually just a few musical notes, was played whenever the station would otherwise be silent (e.g., between the end of a program and the time signal at the top of the hour.) I remember many an interval signal fondly.

But one of them, I just cannot identify. Namely this one:

Bugs the devil out of me.

 Posted by at 7:59 pm
Apr 062017
 

My current phone is a Nexus 6P.

I picked this phone for one all-important reason: It is a “pure Android” phone, directly supported by Google. Which means that instead of being at the manufacturer’s mercy when it comes to updates, I receive monthly security updates from Google. In this day and age, this is a deciding factor for me.

I got the phone in September. Sometime in the winter, I noticed that a speck appeared in photographs taken by the phone’s main camera.

Its appearance suggests that it is a small dust particle stuck between the camera visor and the camera itself, or inside the camera optics perhaps. Others apparently encountered the same issue. Some were able to shake the phone until the speck vanished. I tried to do the same but to no avail. Obviously I do not want to damage or destroy the phone.

I was trying to decide whether or not to live with it. A friend of mine suggested that I should contact the manufacturer since the phone is under warranty. I decided to do just that. Here is the exchange of e-mails that followed:

From: Viktor T. Toth
Sent: Tuesday, April 4, 2017 10:24 PM
To: ‘SupportCanada@huawei.com’ <SupportCanada@huawei.com>
Subject: Nexus 6P warranty issue

Greetings,

I obtained a Nexus 6P from Rogers Canada in September 2016.

A few months ago, I noticed that its camera developed a speck (see attached, lower right corner; the picture is of a uniformly illuminated white sheet of paper). Researching online, I found out that it is not an uncommon problem, and may be due to a loose dust particle inside the camera. Some people had luck shaking the speck lose. I tried gently tapping/shaking the phone, to no avail.

I also learned that this issue may be covered under warranty.

Please enlighten me if this is the case and, if so, how the warranty process works.

Sincerely,

Viktor Toth

Attachment: IMG_20170404_221736.jpg

From: Huawei Device Support [mailto:supportcanada@mail01.huawei.com]
Sent: Wednesday, April 5, 2017 2:41 PM
To: Viktor T. Toth
Subject: Nexus 6P black spot

Dear Mr. Toth, receive a warm greeting.

We widely appreciate the information you provided us, and gladly inform you that on the attachment you can find information concerning your inquiry.

We are at your service.

Best regards.
C.B.W.

Attachment: Black spots on camara.pdf

From: Viktor T. Toth
Sent: Wednesday, April 5, 2017 3:17 PM
To: ‘Huawei Device Support’ <supportcanada@mail01.huawei.com>
Subject: RE: Nexus 6P black spot

Dear Huawei support,

I thank you for your response but I find it quite unacceptable. If you had looked at the image that I sent to you, you would have seen that the “impurity spot” is actually about 100 pixels in diameter and very prominently noticeable in every picture that I take (attached enlarged, cropped image should also appear below):

If this is an acceptable impurity to you, I pity your customers. (This a crop from an actual photo of a white sheet of paper taken by the phone; I did not enlarge or manipulate it in any way.)

I also wonder if you perhaps misunderstood my inquiry and thought that I was referring to the display of the phone, as opposed to its main camera.

I’ll probably learn to live with this speck or attempt a repair. Your response as well as what I read online about your Canadian warranty support gives me little confidence that I can seek help from you.

However, I thank you for reminding me that when it comes to my next phone purchase, I should take into account the manufacturer’s support policy as well as the quality and capabilities of the device when I make my decision. The Nexus 6P may be a premium quality device, but your support perhaps isn’t.

Sincerely,

Viktor Toth

From: Huawei Device Support [mailto:supportcanada@mail01.huawei.com]
Sent: Wednesday, April 5, 2017 6:55 PM
To: Viktor T. Toth
Subject: Huawei Mail Support

Dear Mr. Toth.

We appreciate your preference, and deeply regret any inconvenience that you are experiencing with your Huawei device, however in order to correct this situation, in the attached file you will find a detailed answer to your question.

We are at your service.

Best regards.
C.B.W.


From: Viktor T. Toth
Sent: Wednesday, April 5, 2017 8.02 PM
To: ‘Huawei Device Support’ <supportcanada@mail01.huawei.com>
Subject: RE: Huawei Mail Support

I have not received an attachment in your response to my second inquiry.

Sincerely,

Viktor Toth

From: Huawei Device Support [mailto:supportcanada@mail01.huawei.com]
Sent: Thursday, April 6, 2017 12:43 PM
To: Viktor T. Toth
Subject: Huawei Mail Support

Dear Mr. Toth, receive a warm greeting.

We widely appreciate the information you provided us, and gladly inform you that on the attachment you can find information concerning your inquiry.

We are at your service.

Best regards.
C.B.W.

Attachment: Service Center Information. Toth.pdf

 

Somehow, in light of this exchange, I do not feel particularly confident that it is a good idea to send in my phone for repair.

FYI, Huawei: The long-distance prefix in North America is 1, not 001.

 Posted by at 2:34 pm
Apr 052017
 

I don’t often post pictures of my friends, but this time, I have my friend Perry’s permission.

Perry was flying west the other day. While waiting at the airport, he encountered a familiar face. The familiar face belonged to Canada’s Minister of National Defence, Harjit Singh Sajjan.

The Honourable Minister was probably flying back to his Vancouver riding, which he represents in Parliament.

Whatever the reason, the remarkable thing is this: Mr. Sajjan was traveling the same way most other Canadian would travel. On a commercial airliner, flying coach.

Let me repeat that, this time in boldface: Canada’s Minister of National Defence, traveling cross-country on a commercial airliner, flying coach.

I am so glad Mr. Sajjan allowed Perry to take this selfie, and that Perry kindly permitted me to repost it. This was not a moment designed for publicity. As far as I know, Mr. Sajjan does not publicize the manner in which he travels. He just… does the right thing.

And the other remarkable thing is that he can do this. It speaks volumes about our country and our government.

 Posted by at 12:37 pm
Mar 312017
 

Here is an old friend from the neighborhood that we have known for 12 years already, but whom we haven’t seen since October:

 

But today, he was outside, enjoying the warmth of the early spring sun.

Hello, MJ. It is so good to see you again.

 Posted by at 12:46 am
Mar 072017
 

There is a piece of North American technology that was responsible, among other things, for the “most successful failure” in the history of America’s space program, the successful return of Apollo 13 after a major explosion on board.

A few weeks ago, when chatting with a family member from Hungary who happens to be a proud, freshly minted engineer, I learned, much to my astonishment, that this technology is still not commonly used (if available at all) in Europe.

And today, much to my delight, I found out why: Perhaps it’s because it is still manufactured domestically, in my case right here in Canada.

Here is what I am talking about:

Yes, the mundane duct tape. Proudly made in Canada, as the label on the inside informs me.

It is my understanding that duct tape was included in the emergency repair kit of every American spacecraft launched to date. On Apollo 13, it was with the help of duct tape that they were able to adopt CO2 filters, extending the time they were able to spend in the lunar vehicle, which was used as a lifeboat during the long trip around the Moon.

I am beginning to wonder if this technology should be placed on strategic export control lists. Who knows what duct tape can do in the wrong hands! Imagine Kim Jong Un with a roll of duct tape… or Vladimir Putin. Or Iran’s Revolutionary Guard. The world would be a lot less safe if every despot had free access to copious amounts of duct tape.

Oh well, enough ranting. I need to do something useful, like some vacuuming. Recently, the wand of my vacuum broke. Rather than ordering a costly replacement at a price higher than an old vacuum cleaner is worth, I fixed it and so far, the wand is working like new. As to what I fixed it with, you guessed it… it was duct tape. Works wonders.

 Posted by at 5:18 pm
Jan 312017
 

Here are two contributions from personal experience to the ever growing list of Internet pictures that go with the “You had one job…” meme.

First, a nice loaf of our favorite nine-gain bread, from a neighborhood Portuguese bakery:

Yes, you are seeing it right: It’s sliced lengthwise. Needless to say, the hapless employee who offered this stunning demonstration of human intelligence did not remain on the job much longer. (Regardless of how it was sliced, the bread was yummy.)

Next, one of my favorite deserts, an Austrian delicacy, a Mozartkugel (Mozart ball):

What’s wrong with it, you ask? Well… the portrait of Mozart is not supposed to be on the bottom of the piece, you know; it usually goes on top!

I know, I know, there have been much bigger fails on the Interwebs. Still, I found these funny.

 Posted by at 9:05 pm
Dec 242016
 

Once again, I feel compelled to use the same image and same words that I have been using for many years, to wish all my family, all my friends, indeed everyone on the good Earth a very merry Christmas: the words of the astronauts of Apollo 8.

I know, I know, it’s the same thing every year. But there really aren’t any better words. Just imagine: three human beings, for the first time in human history, far from the Earth, in orbit around another celestial body. And back on Earth, one of the most troubled years in recent history: 1968. So on Christmas Eve, with about a billion people listening—a full one quarter of the Earth’s population at the time—they greeted us Earthlings with the opening passages from the Book of Genesis, the common creation mythology of several major religions.

And then Frank Borman ended the broadcast with words that are as appropriate today as we are heading towards more troubled times as they were back then: “And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas – and God bless all of you, all of you on the good Earth.”

 Posted by at 9:10 am
Dec 182016
 

I have been so busy this week, I forgot to blog about our latest Maxima release, 5.39. Nothing spectacular, just incremental improvements over 5.38; for me, this was a big milestone though as this was the first time that I used a CentOS platform to prepare the release. (Which, incidentally, is why I haven’t done this months ago.)

And SourceForge, kindly enough, once again designated Maxima as one of the site’s Projects of the Week.

 Posted by at 1:23 am
Dec 132016
 

This morning, when I woke up, the regular status e-mails that my servers greet me with told me that there is a major CentOS update (version 7.3). Cool. Unfortunately, it meant that I needed to upgrade as many as five servers. This includes my main server, its physical backup, my backup server in NYC, another “in cloud” backup, and yet another server that I help administer. I began this process shortly after 8 in the morning, after I finished breakfast.

And as usual, a major upgrade like this brings to the surface little problems, little annoyances such as folders that had incorrectly configured SELinux permissions. No big deal, to be sure, but several such little things can consume hours of your time.

And then, it was also Microsoft Patch Tuesday, the second Tuesday of the month when Microsoft releases scheduled updates to Windows and other products. As soon as I was done with CentOS, my attention turned to my Windows machines, including my main workstation, its backup (actually, the same physical machine that also acts as my server’s backup in a dual-boot configuration), my wife’s desktop computer, two laptops, and last but not least, my old desktop that I still keep around as a backup/test computer.

Moreover, I also decided to update three virtual machines (one running Windows 7, the other two, Windows XP) that I keep around both for test purposes but also to have older software, older configurations available if needed.

Furthermore, when I update Windows, I tend to check and see if any other software packages need updating. On some computers, I run Secunia PSI, which keeps track of many applications. But even on other systems, I had to update Java (if installed), Adobe Flash, Chrome and Firefox.

And on older hardware, the process can be painfully slow.

To make a long story short, by the time I finished the bulk of this work, it was 7:30 in the evening. And one computer (a really low powered old netbook) is still doing its thing, even though it’s well past 11 PM now.

No wonder I didn’t accomplish much today.

Of course all of this needed to be done. Since I am a one-man band, I don’t have an IT department to rely on, but it is still important for me to keep my systems secure and well-maintained.

Nonetheless, it feels like one hell of a waste of a day.

 Posted by at 11:22 pm