David Siska
@dsiska.bsky.social
Reader at School of Mathematics, University of Edinburgh; stochastic control, RL, maths of ML https://www.maths.ed.ac.uk/~dsiska/
In Edinburgh they struggle to find each other. 🤣😕
Cycleways can merge? Who knew?
(also, build for the traffic you want)
(also, build for the traffic you want)
Two cycleways merging in the Netherlands makes the cycleway far wider than the road alongside!
May 11, 2025 at 9:43 PM
In Edinburgh they struggle to find each other. 🤣😕
Reposted by David Siska
No other European Capital would “re-open” a 5-lane city centre dual carriageway allowing thru access for public cars when it’s been restricted for years.
It should be “re-opened” with wider pavements, bigger bus stops and be for buses, taxis, bikes and pedestrians only.
A HUGE missed opportunity.
It should be “re-opened” with wider pavements, bigger bus stops and be for buses, taxis, bikes and pedestrians only.
A HUGE missed opportunity.
Restoration of Edinburgh’s North Bridge believed to cost £86m !
But according to our councillors, there’s “no money” for LTNs, pedestrian zones or protected cycle lanes 🤔
All despite them being low cost, highly effective interventions that save money in the long run on health/pollution/potholes
But according to our councillors, there’s “no money” for LTNs, pedestrian zones or protected cycle lanes 🤔
All despite them being low cost, highly effective interventions that save money in the long run on health/pollution/potholes
May 5, 2025 at 5:31 PM
No other European Capital would “re-open” a 5-lane city centre dual carriageway allowing thru access for public cars when it’s been restricted for years.
It should be “re-opened” with wider pavements, bigger bus stops and be for buses, taxis, bikes and pedestrians only.
A HUGE missed opportunity.
It should be “re-opened” with wider pavements, bigger bus stops and be for buses, taxis, bikes and pedestrians only.
A HUGE missed opportunity.
True, but for maths the paper also 100% is on arXiv so just force your search engine to find that copy.
Every now again it’s useful to repeat advice about accessing papers that are behind a paywall that excludes you. Email the author. My estimate is that 90% of academics are so thrilled that a living, breathing, possibly even reading, person shows interest that they will swiftly send you a copy.
May 3, 2025 at 3:28 PM
True, but for maths the paper also 100% is on arXiv so just force your search engine to find that copy.
Reposted by David Siska
"it would require about 31 hectares of corn ethanol to produce the same amount of energy generated by one hectare of land covered in solar panels"
www.anthropocenemagazine.org/2025/04/new-...
www.anthropocenemagazine.org/2025/04/new-...
April 26, 2025 at 2:12 PM
"it would require about 31 hectares of corn ethanol to produce the same amount of energy generated by one hectare of land covered in solar panels"
www.anthropocenemagazine.org/2025/04/new-...
www.anthropocenemagazine.org/2025/04/new-...
Reposted by David Siska
the cost of doing business.
April 24, 2025 at 2:30 PM
the cost of doing business.
Reposted by David Siska
“Children’s worlds have shrunk enormously over the last 50 years… We need to reclaim childhood.”
> More than 80 per cent of 55- to 64-year-olds said they regularly played out on the street and had freedom to explore when they were young, compared with only a quarter of children today.
> More than 80 per cent of 55- to 64-year-olds said they regularly played out on the street and had freedom to explore when they were young, compared with only a quarter of children today.
‘We need to reclaim childhood’: UK ministers urged to restore right to play
A steady erosion of outdoor playtime is impairing the development of infants, say experts
www.ft.com
April 17, 2025 at 1:36 PM
“Children’s worlds have shrunk enormously over the last 50 years… We need to reclaim childhood.”
> More than 80 per cent of 55- to 64-year-olds said they regularly played out on the street and had freedom to explore when they were young, compared with only a quarter of children today.
> More than 80 per cent of 55- to 64-year-olds said they regularly played out on the street and had freedom to explore when they were young, compared with only a quarter of children today.
Reposted by David Siska
Announcing : The 2nd International Summer School on Mathematical Aspects of Data Science
mathsdata2025.github.io
EPFL, Sept 1–5, 2025
Speakers:
Bach @bachfrancis.bsky.social
Bandeira
Mallat
Montanari
Peyré @gabrielpeyre.bsky.social
For PhD students & early-career researchers
Apply before May 15!
mathsdata2025.github.io
EPFL, Sept 1–5, 2025
Speakers:
Bach @bachfrancis.bsky.social
Bandeira
Mallat
Montanari
Peyré @gabrielpeyre.bsky.social
For PhD students & early-career researchers
Apply before May 15!
Mathematical Aspects of Data Science
Graduate Summer School - EPFL - Sept. 1-5, 2025
mathsdata2025.github.io
April 14, 2025 at 5:00 PM
Announcing : The 2nd International Summer School on Mathematical Aspects of Data Science
mathsdata2025.github.io
EPFL, Sept 1–5, 2025
Speakers:
Bach @bachfrancis.bsky.social
Bandeira
Mallat
Montanari
Peyré @gabrielpeyre.bsky.social
For PhD students & early-career researchers
Apply before May 15!
mathsdata2025.github.io
EPFL, Sept 1–5, 2025
Speakers:
Bach @bachfrancis.bsky.social
Bandeira
Mallat
Montanari
Peyré @gabrielpeyre.bsky.social
For PhD students & early-career researchers
Apply before May 15!
Very much true from what I've seen personally and heard from colleagues. Endless forms. Pointless meetings. Flexibility removed from teaching design / delivery by well meaning but finally destructive rules. Students treated as children in pursuit of heeding their "feedback" and improving NSS.
Needless bureaucracy and “bullshit jobs” are preventing academics from fulfilling their core creative responsibilities and making clinical research an “impossible task”, a leading neuroscientist has warned. @patrickjack.bsky.social reports
#AcademicSky
#AcademicSky
‘Mountain of small things’ killing academia, warns Oxford scholar
Overly cautious institutions pushing ‘bullshit jobs’ on their staff ‘destroying academia from within’, says neuroscientist
www.timeshighereducation.com
April 13, 2025 at 1:17 PM
Very much true from what I've seen personally and heard from colleagues. Endless forms. Pointless meetings. Flexibility removed from teaching design / delivery by well meaning but finally destructive rules. Students treated as children in pursuit of heeding their "feedback" and improving NSS.
Reposted by David Siska
🔴‘The Anti-Democratic Tyranny of the Office For Budget Responsibility’
A decades-long trend of outsourcing democratic decisions to unaccountable institutions like the OBR is leading Britain towards ruin, argues Neal Lawson
bylinetimes.com/2025/04/04/t...
A decades-long trend of outsourcing democratic decisions to unaccountable institutions like the OBR is leading Britain towards ruin, argues Neal Lawson
bylinetimes.com/2025/04/04/t...
'The Anti-Democratic Tyranny of the Office For Budget Responsibility'
A decades-long trend of outsourcing democratic decisions to unaccountable institutions like the OBR is leading Britain towards ruin, argues Neal Lawson
bylinetimes.com
April 6, 2025 at 8:42 AM
🔴‘The Anti-Democratic Tyranny of the Office For Budget Responsibility’
A decades-long trend of outsourcing democratic decisions to unaccountable institutions like the OBR is leading Britain towards ruin, argues Neal Lawson
bylinetimes.com/2025/04/04/t...
A decades-long trend of outsourcing democratic decisions to unaccountable institutions like the OBR is leading Britain towards ruin, argues Neal Lawson
bylinetimes.com/2025/04/04/t...
Reposted by David Siska
The classic “George Watson’s” rat run, which is currently severed by modal filters at Braid Ave. The council plan to reopen* this rat run, thereby effectively closing it to children walking, wheeling and cycling
Shameful stuff, that goes against all council policy
Shameful stuff, that goes against all council policy
April 2, 2025 at 9:28 AM
The classic “George Watson’s” rat run, which is currently severed by modal filters at Braid Ave. The council plan to reopen* this rat run, thereby effectively closing it to children walking, wheeling and cycling
Shameful stuff, that goes against all council policy
Shameful stuff, that goes against all council policy
Reposted by David Siska
We now have super new planters at the traffic filter on Whitehouse Loan! Looks so much better
Thank you
@edinburghcouncil.bsky.social
@cllrbenparker.bsky.social
@stephenjenkinson.bsky.social
Thank you
@edinburghcouncil.bsky.social
@cllrbenparker.bsky.social
@stephenjenkinson.bsky.social
March 26, 2025 at 2:36 PM
We now have super new planters at the traffic filter on Whitehouse Loan! Looks so much better
Thank you
@edinburghcouncil.bsky.social
@cllrbenparker.bsky.social
@stephenjenkinson.bsky.social
Thank you
@edinburghcouncil.bsky.social
@cllrbenparker.bsky.social
@stephenjenkinson.bsky.social
Reposted by David Siska
The La Crosse Tribune, July 08, 1924
March 25, 2025 at 6:31 PM
The La Crosse Tribune, July 08, 1924
Reposted by David Siska
Why we need more than “timed closures” outside schools.
Streets come alive when opened to people
Where is the voice of the children in the debate on this?
Streets come alive when opened to people
Where is the voice of the children in the debate on this?
A school street in Paris when there is no school (video from 2023)
March 24, 2025 at 12:08 PM
Why we need more than “timed closures” outside schools.
Streets come alive when opened to people
Where is the voice of the children in the debate on this?
Streets come alive when opened to people
Where is the voice of the children in the debate on this?
Reposted by David Siska
Madrid did this in 12 years! This is the same timeframe it takes Edinburgh to build…
…one (1) segregated cycle lane 🤔
When councillors sit smugly on their bums, prevaricating, delaying & filibustering, they are FAILING the people of Edinburgh
…one (1) segregated cycle lane 🤔
When councillors sit smugly on their bums, prevaricating, delaying & filibustering, they are FAILING the people of Edinburgh
Between 1995 and 2007, Madrid tripled its metro network by adding 127 miles of track and 157 stations at a cost of $12.5 billion.
In Canada/USA, subway construction costs average more than $1 billion per mile. If we could build at scale and at a lower cost, we'd be unstoppable.
In Canada/USA, subway construction costs average more than $1 billion per mile. If we could build at scale and at a lower cost, we'd be unstoppable.
March 21, 2025 at 4:22 PM
Madrid did this in 12 years! This is the same timeframe it takes Edinburgh to build…
…one (1) segregated cycle lane 🤔
When councillors sit smugly on their bums, prevaricating, delaying & filibustering, they are FAILING the people of Edinburgh
…one (1) segregated cycle lane 🤔
When councillors sit smugly on their bums, prevaricating, delaying & filibustering, they are FAILING the people of Edinburgh
Reposted by David Siska
Fractional Brownian motion, varying the Hurst parameter H between 0 and 1. H=0.5 corresponds with standard Brownian motion, and the path has fractal dimension 2-H
March 21, 2025 at 1:22 AM
Fractional Brownian motion, varying the Hurst parameter H between 0 and 1. H=0.5 corresponds with standard Brownian motion, and the path has fractal dimension 2-H
Reposted by David Siska
Lunar eclipses, such as the one yesterday, were one of the earliest pieces of scientific evidence that the Earth was basically a round sphere, already known to Aristotle: regardless of the position of the eclipse in the light sky, the shadow of the Earth on the Moon was always circular.
March 14, 2025 at 9:51 PM
Lunar eclipses, such as the one yesterday, were one of the earliest pieces of scientific evidence that the Earth was basically a round sphere, already known to Aristotle: regardless of the position of the eclipse in the light sky, the shadow of the Earth on the Moon was always circular.
Reposted by David Siska
Probably not too big of a deal that right now there's the least amount of ice on our planet's surface in recorded human history
March 7, 2025 at 8:10 PM
Probably not too big of a deal that right now there's the least amount of ice on our planet's surface in recorded human history
Reposted by David Siska
In my Substack today I look at some of the key insights from the UK Climate Change Committee's Seventh Carbon Budget.
www.sustainabilitybynumbers.com/p/uk-ccc-sev...
www.sustainabilitybynumbers.com/p/uk-ccc-sev...
Some key insights from the UK Climate Change Committee’s Seventh Carbon Budget
What would it take for the UK to get to net-zero by 2050?
www.sustainabilitybynumbers.com
March 6, 2025 at 9:36 AM
In my Substack today I look at some of the key insights from the UK Climate Change Committee's Seventh Carbon Budget.
www.sustainabilitybynumbers.com/p/uk-ccc-sev...
www.sustainabilitybynumbers.com/p/uk-ccc-sev...
Reposted by David Siska
March 3, 2025 at 12:53 PM
Reposted by David Siska
I am happy to announce that the Kakeya set conjecture, one of the most sought after open problems in geometric measure theory, has now been proven (in three dimensions) by Hong Wang and Joshua Zahl! arxiv.org/abs/2502.17655 I discuss some ideas of the proof at terrytao.wordpress.com/2025/02/25/t...
Volume estimates for unions of convex sets, and the Kakeya set conjecture in three dimensions
We study sets of $δ$ tubes in $\mathbb{R}^3$, with the property that not too many tubes can be contained inside a common convex set $V$. We show that the union of tubes from such a set must have almos...
arxiv.org
February 26, 2025 at 4:49 AM
I am happy to announce that the Kakeya set conjecture, one of the most sought after open problems in geometric measure theory, has now been proven (in three dimensions) by Hong Wang and Joshua Zahl! arxiv.org/abs/2502.17655 I discuss some ideas of the proof at terrytao.wordpress.com/2025/02/25/t...
Reposted by David Siska
It's lovely and windy today, which means lots of clean green electricity.
Or does it? See all those purple dots in Scotland? Those are wind farms that we're turning off as of 8am… 🤔
Or does it? See all those purple dots in Scotland? Those are wind farms that we're turning off as of 8am… 🤔
February 21, 2025 at 1:39 PM
It's lovely and windy today, which means lots of clean green electricity.
Or does it? See all those purple dots in Scotland? Those are wind farms that we're turning off as of 8am… 🤔
Or does it? See all those purple dots in Scotland? Those are wind farms that we're turning off as of 8am… 🤔
I say no more research on biased estimators, differential inclusions, inequalities… down with that sort of stuff.
🚨BREAKING. From a program officer at the National Science Foundation, a list of keywords that can cause a grant to be pulled. I will be sharing screenshots of these keywords along with a decision tree. Please share widely. This is a crisis for academic freedom & science.
February 4, 2025 at 8:38 PM
I say no more research on biased estimators, differential inclusions, inequalities… down with that sort of stuff.
Very nice! Perfect for Saturday afternoon.
February 1, 2025 at 5:08 PM
Very nice! Perfect for Saturday afternoon.