1963 and all that…

Posted in Biographical with tags , , on June 4, 2014 by telescoper

original_events-of-1963-51st-birthday-ladies-t-shirt

The Day in Pictures

Posted in Biographical, Education on June 3, 2014 by telescoper

Just back home from Milan after a pretty long day, the story of which is told in the three photographs.

First of all, congratulations to Dr Eleonora Villa, who successfully defended her thesis this afternoon! The intriguing cover picture on the glossy copy shown is of course by Wassily Kandinsky

Then there’s my old apartment at No. 19 Via Beato Angelico which I successfully located after getting lost only twice. It is on the right of the building, on the second floor, with the balcony. The graffiti weren’t there when I was resident in 1994 but otherwise the area hasn’t changed much.

 

And finally there’s the shambolic overcrowding in the UKBA section of Heathrow Terminal 5 that delayed my return home by about an hour…

Via Beato Angelico

Posted in Biographical, Education with tags , , , , , on June 2, 2014 by telescoper

So here I am, then, in Milan(o). I’m just here for a short visit in order to participate in a PhD examination tomorrow at the Universita Degli Studi di Milano. I’m looking forward to it, actually, as I’ve never done such an examination in the Italian system before. It will also give me the chance to meet up with a couple of old friends I haven’t seen for a while before flying back to London tomorrow night.

I don’t know if I’ve mentioned this before on this blog but I was a fairly long-term resident in Milan some years ago. In fact I’ve just checked the dates and it was in 1994, i.e. twenty years ago. Time flies indeed. All those years ago I was here as a Professore a Contratto, which means I gave some lectures and did a small research project. The invitation for this came via Silvio Bonometto. I didn’t get paid a huge amount for this visit, but as part of the deal I did get use of an apartment organized by the University. It was on the Via Beato Angelico and this photograph, which I have just ripped off from my own facebook page, shows the view from the balcony:

Via Beato Angelico

It was a nice enough flat and in a good location just around the corner from the University. The one thing I remember well is that one of the main tram lines ran along the street below; their sound has stuck with me through the years, as they often woke me up very early in the morning. I think there was an ice cream place over the road too.

During my stay here I was accompanied by a friend, Anna, whom I invited to come when they told me I was going to have use of an apartment. Anna wanted to try to find a job in Italy so it seemed a great chance to spend three months or so looking around while I worked. The place was easily big enough for two and I was grateful for the company in the evenings. We had a lot of fun doing the tourist things, visiting night clubs, and the rest. Most people thought we were an item, I suppose, but we weren’t. Her long red hair gave her the nickname Anna Dai Cappelli Rossi, after the cartoon character. Here is a picture of Anna I took on the roof of the Duomo:

Anna

Anyway, when it was time for me to return to England, Anna stayed in Milan because she had found a job (and a man). She did return to England though and now lives in the Midlands in a place called Liverpool.

I’m mentioning all this because the hotel I’m now staying in, the Hotel Dieci, is just a short walk from that old place. I’ll probably have enough time in the morning to take a walk past and see if I can find it. I wonder how much the area around here has changed in the last twenty years? I’ll have time to find out tomorrow but for tonight I had better read the thesis again!

Out of Power

Posted in Biographical with tags , , on June 1, 2014 by telescoper

I had quite a few things to do on campus today before jetting off on a short trip tomorrow. I hoped to finish them in time for a decent blog post before heading home for tea and the Beelzebub crossword. Unfortunately when I got to the University just after 1pm I found the building in darkness. It turns out that the power went off about 10am. A little investigation revealed that all the buildings North-South Road (that’s the part of the Sussex University campus where all the science buildings are located) had a complete power outage due to a probably probably due to a fault in the high-voltage supply onto campus. Engineers had been called out as soon as the fault was reported but, not being qualified to work on such equipment themselves, power wasn’t restored until just after 4pm with the arrival of a specialist crew.

One thing worth saying about this is that the School of Mathematical and Physical Sciences does have an emergency response procedure for such eventualities and since as Head of School I’m officially a “responsible person” I had to make a judgement as to whether there was a serious threat to safety. If there had been, I would have had to execute the plan, contact all the relevant personnel, and order people out of the building. I decided that there wasn’t so just informed the students who were in the building what the situation was and that they could stay if they wanted. The emergency lighting was working and there was no immediate danger of anything nasty happening.

I went for a stroll around campus to see the extent of the outage. The only sign of life nearby was the sound from the emergency generators in the Shawcross building which kicked in to keep the main campus servers up and running. The PC room at the front of the building was deserted. Presumably the students who usually work there at weekends had found an alternative location, or were just outside enjoying the sunshine until the systems started up again, and any staff in attendance were presumably working on the backup systems in the bowels of the building.

No computers were working in our building either of course so some decided to work in the Library, which is on the other side of campus and wasn’t affected by the power cut. After checking out with the campus services what was going on I decided to stay until the fault was rectified just in case there were any problems. Some of our physicists had experiments running over the weekend and one or two came in to check that there was no serious harm done to their gear. There may be some faults to deal with tomorrow morning, but by then I’ll be elsewhere!

Such things as power cuts are inconvenient but they remind us how dependent we have become on electricity, especially for running computers. Fortunately this happened on a Sunday so there wasn’t much happening on campus, but a huge amount of our activities rely on digital devices of one form or another and it would have been much worse had it happened on a week day. The worst thing as far as I’m concerned, however, is that with no computer to work on I was deprived of displacement activities and was forced to start marking the scripts from Theoretical Physics examination…

Beards, Shorts & Sandals Code for 2014 Season

Posted in Beards, Biographical on June 1, 2014 by telescoper

The Beard, Shorts and Sandals season is officially open and I’ve been observing the relevant guidelines rigorously today…

kmflett's avatarKmflett's Blog

Beard Liberation Front

Communique 1st June

‘BEARDS, SHORTS & SANDALS’ CODE FOR 2014 SEASON

The Beard Liberation Front, the informal network of beard wearers, has said that as June starts it is issuing a reminder about the code for the 2014 Beards, Shorts and Sandals season which runs until the end of August.

Adherence to the guidelines is important if the beard wearer is to safely wear shorts and sandals in public during the summer months

2014 Code

1] Shorts and sandals may be worn after midday until 8pm at the discretion of the wearer.

2] Where sandals are worn the wearing of socks is discouraged but not forbidden

3] If socks are not worn toenails must be neat, trimmed, clean and fungus free

4] Shorts should ideally be around knee length to provide a balanced image with the beard

5] Shorts should be of conservative design and colour…

View original post 112 more words

The Cake Equation

Posted in The Universe and Stuff with tags , , , on May 31, 2014 by telescoper

Yesterday being the last Friday of the month of May it was time for another tea-and-cake event in the School of Mathematical and Physical Sciences. These provide an opportunity for staff to get together and chat while demolishing a specially-themed cake. The cakes themselves are organized by the inestimable Miss Lemon and I never know what the theme is before the goods arrive, so I have to ad lib a short introduction (for just a minute, without repetition, hesitation, deviation or repetition) before cutting the cake.

As you will observe, this time the (Lemon Drizzle) cake was decorated with the Dirac Equation (which I consider to be the most beautiful equation in physics)..

On the Pulse of Morning

Posted in Poetry with tags , , on May 30, 2014 by telescoper

A Rock, A River, A Tree
Hosts to species long since departed,
Marked the mastodon.
The dinosaur, who left dry tokens
Of their sojourn here
On our planet floor,
Any broad alarm of their hastening doom
Is lost in the gloom of dust and ages.

But today, the Rock cries out to us, clearly, forcefully,
Come, you may stand upon my
Back and face your distant destiny,
But seek no haven in my shadow.

I will give you no more hiding place down here.

You, created only a little lower than
The angels, have crouched too long in
The bruising darkness,
Have lain too long
Face down in ignorance.

Your mouths spilling words
Armed for slaughter.

The Rock cries out today, you may stand on me,
But do not hide your face.

Across the wall of the world,
A River sings a beautiful song,
Come rest here by my side.

Each of you a bordered country,
Delicate and strangely made proud,
Yet thrusting perpetually under siege.

Your armed struggles for profit
Have left collars of waste upon
My shore, currents of debris upon my breast.

Yet, today I call you to my riverside,
If you will study war no more. Come,

Clad in peace and I will sing the songs
The Creator gave to me when I and the
Tree and the stone were one.

Before cynicism was a bloody sear across your
Brow and when you yet knew you still
Knew nothing.

The River sings and sings on.

There is a true yearning to respond to
The singing River and the wise Rock.

So say the Asian, the Hispanic, the Jew
The African and Native American, the Sioux,
The Catholic, the Muslim, the French, the Greek
The Irish, the Rabbi, the Priest, the Sheikh,
The Gay, the Straight, the Preacher,
The privileged, the homeless, the Teacher.
They hear. They all hear
The speaking of the Tree.

Today, the first and last of every Tree
Speaks to humankind. Come to me, here beside the River.

Plant yourself beside me, here beside the River.

Each of you, descendant of some passed
On traveller, has been paid for.

You, who gave me my first name, you
Pawnee, Apache and Seneca, you
Cherokee Nation, who rested with me, then
Forced on bloody feet, left me to the employment of
Other seekers- desperate for gain,
Starving for gold.

You, the Turk, the Swede, the German, the Scot…
You the Ashanti, the Yoruba, the Kru, bought
Sold, stolen, arriving on a nightmare
Praying for a dream.

Here, root yourselves beside me.

I am the Tree planted by the River,
Which will not be moved.

I, the Rock, I the River, I the Tree
I am yours- your Passages have been paid.

Lift up your faces, you have a piercing need
For this bright morning dawning for you.

History, despite its wrenching pain,
Cannot be unlived, and if faced
With courage, need not be lived again.

Lift up your eyes upon
The day breaking for you.

Give birth again
To the dream.

Women, children, men,
Take it into the palms of your hands.

Mold it into the shape of your most
Private need. Sculpt it into
The image of your most public self.
Lift up your hearts
Each new hour holds new chances
For new beginnings.

Do not be wedded forever
To fear, yoked eternally
To brutishness.

The horizon leans forward,
Offering you space to place new steps of change.
Here, on the pulse of this fine day
You may have the courage
To look up and out upon me, the
Rock, the River, the Tree, your country.

No less to Midas than the mendicant.

No less to you now than the mastodon then.

Here on the pulse of this new day
You may have the grace to look up and out
And into your sister’s eyes, into
Your brother’s face, your country
And say simply
Very simply
With hope
Good morning.

by Maya Angelou (4th April 1928-28th May 2014; Rest in Peace)

 

BICEP2: The Dust Thickens…

Posted in The Universe and Stuff with tags , , , , , , on May 29, 2014 by telescoper

Off to a day-long staff training event today so just time to post a quick update on the BICEP2 saga (see various posts on this blog). There’s a new paper on the arXiv today by Flauger, Hill and Spergel. The first part of its rather lengthy abstract reads:

BICEP2 has reported the detection of a degree-scale B-mode polarization pattern in the Cosmic Microwave Background (CMB) and has interpreted the measurement as evidence for primordial gravitational waves. Motivated by the profound importance of the discovery of gravitational waves from the early Universe, we examine to what extent a combination of Galactic foregrounds and lensed E-modes could be responsible for the signal. We reanalyze the BICEP2 results and show that the 100×150 GHz and 150×150 GHz data are consistent with a cosmology with r=0.2 and negligible foregrounds, but also with a cosmology with r=0 and a significant dust polarization signal. We give independent estimates of the dust polarization signal in the BICEP2 region using four different approaches. While these approaches are consistent with each other, the expected amplitude of the dust polarization power spectrum remains uncertain by about a factor of three. The lower end of the prediction leaves room for a primordial contribution, but at the higher end the dust in combination with the standard CMB lensing signal could account for the BICEP2 observations, without requiring the existence of primordial gravitational waves. By measuring the cross-correlations between the pre-Planck templates used in the BICEP2 analysis and between different versions of a data-based template, we emphasize that cross-correlations between models are very sensitive to noise in the polarization angles and that measured cross-correlations are likely underestimates of the contribution of foregrounds to the map. These results suggest that BICEP1 and BICEP2 data alone cannot distinguish between foregrounds and a primordial gravitational wave signal, and that future Keck Array observations at 100 GHz and Planck observations at higher frequencies will be crucial to determine whether the signal is of primordial origin. (abridged)

The foreground analysis done in this paper seems to me to be much more convincing that that presented in the original BICEP2 paper and it confirms that the data as presented can not discriminate between B-modes arising from a polarized foreground component and from the presence of primordial gravitational waves. As I’ve said before (several times now), the press hype surrounding this discovery was a bit premature and we have to wait for observations at other frequencies before a clearer picture emerges through the dust.

UPDATE: A new Nature News and Views Article contains a strong statement by David Spergel to the effect that BICEP2 provides no evidence either for or against the existence of primordial gravitational waves.

Uncertain Attitudes

Posted in Bad Statistics, Politics with tags , , , , on May 28, 2014 by telescoper

It’s been a while since I posted anything in the bad statistics file, but an article in today’s Grauniad has now given me an opportunity to rectify that omission.
The piece concerned, entitled Racism on the rise in Britain is based on some new data from the British Social Attitudes survey; the full report can be found here (PDF). The main result is shown in this graph:

Racism_graph

The version of this plot shown in the Guardian piece has the smoothed long-term trend (the blue curve, based on a five-year moving average of the data and clearly generally downward since 1986) removed.

In any case the report, as is sadly almost always the case in surveys of this kind, neglects any mention of the statistical uncertainty in the survey. In fact the last point is based on a sample of 2149 respondents. Suppose the fraction of the population describing themselves as having some prejudice is p. For a sample of size n with x respondents indicating that they describe themselves as “very prejudiced or a little prejudiced” then one can straightforwardly estimate p \simeq x/n. So far so good, as long as there is no bias induced by the form of the question asked nor in the selection of the sample…

However, a little bit of mathematics involving the binomial distribution yields an answer for the uncertainty in this estimate of p in terms of the sampling error:

\sigma = \sqrt{\frac{p(1-p)}{n}}

For the sample size given, and a value p \simeq 0.35 this amounts to a standard error of about 1%. About 95% of samples drawn from a population in which the true fraction is p will yield an estimate within p \pm 2\sigma, i.e. within about 2% of the true figure. This is consistent with the “noise” on the unsmoothed curve and it shows that the year-on-year variation shown in the unsmoothed graph is largely attributable to sampling uncertainty; note that the sample sizes vary from year to year too. The results for 2012 and 2013 are 26% and 30% exactly, which differ by 4% and are therefore explicable solely in terms of sampling fluctuations.

I don’t know whether racial prejudice is on the rise in the UK or not, nor even how accurately such attitudes are measured by such surveys in the first place, but there’s no evidence in these data of any significant change over the past year. Given the behaviour of the smoothed data however, there is evidence that in the very long term the fraction of population identifying themselves as prejudiced is actually falling.

Newspapers however rarely let proper statistics get in the way of a good story, even to the extent of removing evidence that contradicts their own prejudice.

The 2014 Shaw Prize for Astronomy

Posted in The Universe and Stuff with tags , , , on May 27, 2014 by telescoper

So I came back to Brighton this morning after a nice long weekend in Cardiff. I took the 6.28 train via Southampton to avoid London and got to the University of Sussex in time to chair the University Human Resources Committee, the usual Chair being unwell. Anyway, all this means that I’ve been a bit busy this afternoon and also a bit tired all of which adds up to no time for a long post.

Fortunately, some nice news appeared to give me a topic for a very quick blog post. Earlier today the winners were announced for the 2014 Shaw Prize in Astronomy. This year’s award actually goes to three cosmologists, Daniel Eisenstein from Harvard, Shaun Cole from Durham  and John Peacock from Edinburgh. The prize of a cool $1Million goes 50% to Eisenstein; the other half is shared equally between Shaun and John. Nice to see another British success!

The citation reads

for their contributions to the measurements of features in the large-scale structure of galaxies used to constrain the cosmological model including baryon acoustic oscillations and redshift-space distortions.

It seems clear that John and Shaun were awarded their half of the prize because of their important work on the Anglo-Australian Two Degree Field Galaxy Redshift Survey (2dFGRS) and Daniel for leading a corresponding analysis of data derived from a survey of Luminous Red Galaxies from the Sloan Digital Sky Survey.

It’s a bit of a coincidence that baryon acoustic oscillations cropped up in this work, after my post last week about Sakharov Oscillations!

Anyway, congratulations to all three winners. No doubt they’ll be buying a few celebratory drinks for their colleagues in the very near future…