Physicist at Civan Lasers
Israel
Joined September 2021
- Tweets2K
- Following178
- Followers51
- Likes39.7K
Pinned Tweet
Check out my recent talk about quantum wavefront shaping :)
youtube.com/watch?v=ZtcKvzpr…
Full paper here: arxiv.org/abs/2505.02221
Check out my new paper on the "Two-Photon Bandwidth of Hyper-Entangled Photons in Complex Media"
Check out our new preprint on the "Two-Photon Bandwidth of Hyper-Entangled Photons in Complex Media"! @RonenShekel @OhadLib @WFShaping @BrombergYaron
We show that the bandwidth of hyper-entangled photons is much larger than their classical counterpart. A thread 🧵.
Ronen Shekel retweeted
Our paper has just been published on APL photonics, and has been chosen as a featured article!
Check out the new section, discussing how these results apply for a state that is not maximally entangled.
link below
Check out our new preprint on the Fundamental Bounds of Wavefront Shaping of Spatially Entangled Photons!
@RonenShekel @WFShaping @BrombergYaron
We show that classical wavefront shaping does not tell the whole story. A thread 🧵.
Interested in wavefront shaping? How about quantum wavefront shaping?
Check out my new preprint on the Fundamental bounds of Wavefront Shaping of Spatially Entangled Photons!
Check out our new preprint on the Fundamental Bounds of Wavefront Shaping of Spatially Entangled Photons!
@RonenShekel @WFShaping @BrombergYaron
We show that classical wavefront shaping does not tell the whole story. A thread 🧵.
Link: arxiv.org/abs/2505.02221
Ronen Shekel retweeted
Our new paper on high-dimensional quantum key distribution is out! nature.com/articles/s41534-0…
@KfirSulimany et al. demonstrate a protocol that doubles the secure key rate of deployed QKD systems. Best of all, it’s just a software update, no hardware modifications are needed!
Ronen Shekel retweeted
1/ We all know that if I can see your eyes, you can see mine. This is thanks to the optical *reciprocity principle*, which states that light paths are reversible. But what if there’s a scattering medium between us, like fog? Can reciprocity still help us “see”? 👁️👁️#Physics
Ronen Shekel retweeted
1/ גוגל דיפמיינד חשפה מודל בינה מלאכותית חדש שמביא פריצת דרך בחיזוי מזג האוויר. מדובר בקפיצה של 50 שנים קדימה, עם דיוק חסר תקדים. למה זה משנה? סיפור קצר:
Ronen Shekel retweeted
New article online: Resource-efficient photonic quantum computation with high-dimensional cluster states.
go.nature.com/4eKkuGx
Ronen Shekel retweeted
🚨🚨Want to know what it's like being investigated by @Columbia for speaking up against support for anti-Jewish, anti-Israeli, and anti-American terrorism on campus?🚨🚨
Here's the email I just sent the university.
This is why you always keep the receipts.
(Would appreciate if you could share this, so other people being investigated at their universities for speaking up can see that they're not alone)
**
Dear President of @Columbia University Katrina Armstrong, COO Cas Holloway, Dean of Columbia Business School (@Columbia_Biz) Costis Maglaras, Associate Director of the Office of Equal Opportunity and Affirmative Action (EOAA) Luisanne Liz, Associate Director of Investigations in the Office of EOAA Sarah Kinney, and General Counsel Felice Rosan,
I am writing to you in regards to the ongoing, prolonged, and retaliatory investigation that Columbia University, through the office of the EOAA, has been waging against me.
On February 8, I was notified by Ms. Sarah Kinney, the Associate Director of the Office of EOAA, that I am being investigated due to a Title IX complaint. Ms. Kinney refused to share the nature of the complaint and the identity of the complainants with me and my lawyers, thus denying me the right to face my accusers and impeding my ability to defend myself and prove my innocence.
The formal policy of the office of EOAA regarding Title IX Grievances is to "conclude no later than 120 calendar days after the University receives the Title IX Formal Complaint". As I am writing this, it has been 278 (!) days since I received that original notice and many more since the university received the formal complaint.
On May 29, I was investigated by two lawyers from Sher Termonte (Ms. Theresa Trzaskom and Mr. Doug Jensen; @SherTremonte) - the law firm hired to do Columbia's dirty work. At the end of a grueling eight hour session, these lawyers assured me that the investigation will be concluded within three weeks. It has been 168 days since I was told that.
On June 27 I emailed Ms. Theresa Trzaskom and Mr. Doug Jensen to voice my concern about the needless pronling of this baseless investigation. On July 9, almost two weeks after sending my email, I received a response from Ms. Trzaskom stating that they hope to complete the investigation "before the end of the month". It has been 3.5 months since the end of July.
On August 5, I emailed then President Minouche Shafik, Executive VP Dennis Mitchell, COO Cas Holloway, General Counsel Felice Rosan, Dean of Columbia Business School Costis Maglaras, Associate Director of Investigations in the Office of EOAA Sarah Kinney, and Columbia's lawyers about my concerns regarding the prolonged investigation. The following day, I received a response from Ms. Theresa Trzaskoma, that "we have completed our investigation and are finalizing our report now." It has been 98 days since I was told that.
On September 13, my lawyers from Kassowitz, Benson, and Torres were informed by Ms. Theresa Trzaskoma that they had completed their report and had sent it to Columbia's Office of EOAA, that they had involved Luisanne Liz, the Associate Director of the Office of Equal Opportunity and Affirmative Action, and that the decision is now at the hands of the university. It has been 60 days since we were told that. I haven't heard anything since.
I would like to remind you that the Office of Equal Opportunity and Affirmative Action is required to send updates every 30 days to the targets of their investigations. Throughout the entire investigation, the office of EOAA has failed to follow it's own procedures, thus denying me the due process that I believe is required of a federally-funded university.
Being wrongly accused and the target of a baseless investigation has been difficult enough without these needless delays. As I have noted in my previous correspondence, the investigators have been evasive and opaque and have resorted to extremely questionable practices that are unbecoming of a law firm hired to investigate one of your employees.
Unfortunately, Columbia's failure to conclude this investigation has created irreparable harm to my reputation in traditional and social media. I am thus emailing you with a demand to immediately bring this investigation to an end and publicly clear my name.
Never in my life had I imagined that Columbia University would stoop so low as to engage in Kafkaesque procedures in order to retaliate against my speaking out for the Jewish people and against support for anti-Jewish, anti-Israeli, and anti-American terrorism on campus.
As an employee of the university, I would appreciate a reply, if only to be acknowledged for my humanity.
Sincerely,
Shai Davidai
CC: @WaysandMeansGOP
CC: @EdWorkforceCmte
Ronen Shekel retweeted
I am going to seek approval from the board of Pershing Square Holdings— in which I and my family own 23% of the shares—to eliminate its listing on the @euronext Amsterdam exchange.
The board had been considering the move because our second listing on the @LSEplc now represents more than 90% of our trading. Events in Amsterdam during the last 24 hours provide an appropriate tipping point for this conclusion.
Concentrating the listing on one exchange, the LSE, and leaving a jurisdiction that fails to protect its tourists and minority populations combine both good business and moral principles. We can also save money and improve liquidity for shareholders to boot.
I have also begun the conversation with @UMG (on whose board I sit) which is domiciled in Amsterdam as well as listed there, about moving its domicile and its listing to the United States, which will offer similar as well as other highly material benefits.
Pershing Square has a contractual right to cause UMG to be listed in the US. We will exercise this right and achieve a US listing for UMG no later than some time next year.
UMG trades at a large discount to its intrinsic value with limited liquidity in significant part due to it not having its primary listing on the @NYSE or @NasdaqExchange and not being eligible for S&P 500 and other index inclusion.
We are going to fix this. Now is a good and appropriate time to do so.
Ronen Shekel retweeted
This is not true. The truth is stranger and more interesting.
Israel still runs its marriage laws according to the Ottoman Empire’s millet system, in which minority communities self-govern through officially recognized religious bodies.
So does Lebanon, by the way. So do other parts of the Middle East. With differences in each place and some changes over time, it’s still fundamentally the old Ottoman way of doing things.
So the only fully recognized state-approved marriage is thus religious marriage controlled by religious conservatives.
And since Jewish religious law doesn’t allow it, Jews can’t marry non-Jews in the official rabbinate.
But here’s where it gets weird: Muslim sharia courts in Israel, also funded and appointed by the state, *can* marry Jews and Muslims - as long as the Muslim is the man. Why? For the same Ottoman logic: because Muslim religious law allows Muslim men (but only men) to marry Jewish or Christian women.
There are also Catholic canon law courts, Druze religious courts, etc. Each community has one.
The Ottoman millet system.
Why does this system survive, especially given polls that does that most Israelis don’t want this system?
Two reasons.
1. We can’t agree on what would replace it. It’s part of our larger secular-religious culture war.
2. We don’t actually live in this system unless we want to.
Because alongside this most restrictive of marriage laws in the free world, another less formal system operates, available to all, accepting of all, including LGBT and interfaith and every combination thereof.
That second system is called “yeduim betzibur” in Hebrew, or “known in public.” It’s essentially what Westerners would call common-law marriage.
And it’s comprehensive, granting a broad cross-section of marriage rights, including to interfaith and same-sex couples, since the 1990s. For example, inheritance, end-of-life decisions for each other, adopting kids together.
Until 2014, when gay marriage became universal in America, Israel was ahead of most of America in terms of specific rights granted to gays - i.e., the most illiberal *formal* marriage law system in the free world sat atop one the most liberal *de facto* marriage law system in the free world.
As I said, strange and interesting.
The current speaker of the Knesset, for example, a powerful conservative politician from Likud, is a married gay man with kids.
This year, because of the war, same-sex partners of soldiers hurt or killed in the war became officially recognized partners for the purposes of military stipends.
My wife and I, two children of rabbis, don’t like the religious rabbinate system, so we married outside it. But we’re still married in the eyes of the state and of everyone we know, including Haredi friends who were at our wedding. Nobody bats an eyelash when you marry outside the official system.
The gap between the old formal system and the lived reality is profound.
Finally, there’s a third option: Marrying abroad. It’s a 45-minute plane ride to Cyprus, which does a brisk business marrying Israelis at Larnaca city hall. Israel is obligated by international treaties to recognize those marriages.
And sitting next to those Israelis in the waiting room? Lebanese couples who are there for the same reason.
When anti-Israel people go after us on questions like this - on those places where we don’t fit the Western liberal norm - it’s nearly always for things that reflect our deep cultural roots in the Middle East. We’re a complicated and sometimes tense mixture of two civilizational worlds. Literally. Half of Israeli Jews hail from Europe, half from Islamic lands.
It makes more sense on these kinds of social questions to think of us as a less dysfunctional Lebanon than as a darker-skinned Switzerland.
If, as Saturday Night Live wants you to believe, the Arab Middle East will soon turn gay-friendly if everyone “stops bombing us,” that liberal Arabness will look like Israel.
Ronen Shekel retweeted
The Wikipedia article on Zionism is riddled with inaccuracies and misleading claims. Prof. Eric Mechoulan, a distinguished historian, critically analyzes its portrayal of Zionism as merely an ethnocultural nationalist movement emerging in 19th-century Europe.
He argues this perspective neglects the deep historical connection of Jews to their ancestral land, Zionism’s response to exile, and the complexities of Jewish identity.
Prof. Mechoulan emphasizes that the article distorts the true essence of Zionism and its historical significance.
Prof. Mechoulan emphasizes that the article distorts the true essence of Zionism and its historical significance.
The accompanying table highlights the contrast between Wikipedia’s misrepresentations and historical facts.
It is time to restore neutrality to Wikipedia and for the @Wikimedia foundation to investigate who is behind the political bias in the editing of this article.
#WikiWashing #Wikibias
Ronen Shekel retweeted
Excited to share our work on high-dimensional quantum key distribution using the orbital angular momentum of single photons from a colloidal quantum dot at room temperature! Let's dive into why this matters for secure communications. A 🧵
opg.optica.org/opticaq/fullt…
Ronen Shekel retweeted
Having listened to the arguments of both sides over the last year, I'm no longer on the fence about Israel's war. Here is why:
Ronen Shekel retweeted
Interested in controlling multiple spatial modes of light? Check out our new tutorial on how to turn your SLM into a 10-plane light converter!
arxiv.org/abs/2409.20039
Ronen Shekel retweeted
Check out our new @NaturePhotonics paper on the generation of cluster states at record-high rates using high-dimensional entanglement:
nature.com/articles/s41566-0…
We use spatial entanglement to reduce the number of photons and feed-forward steps in photonic quantum computation (a 🧵)
Ronen Shekel retweeted
Check out our work on shaping entangled photons using classical feedback!
opg.optica.org/opticaq/fullt…
@RonenShekel and @OhadLib show how we utilize Klyshko’s advanced wave picture, to compensate for scattering of entangled photons through an arbitrary medium (a thread🧵)
