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Wednesday, November 20, 2024

 

Zionism: In the Words of the Leading Zionists and their Allies




Nearly all of these quotes are gathered from the chapter epigraphs in the book, M. Shahid Alam, Israeli Exceptionalism: The Destabilizing Logic of Zionism (Springer: 2008). A few of the quotes are from non-Zionists. The sources for most these quotes can be found in this book.

 Chosenness

“Israel is not another example of the species nation; it is the only example of the species Israel.” Martin Buber

“Only Israel lives in, and constitutes, God’s kingdom…” Jacob Neusner

“For me the supreme morality is that the Jewish people has a right to exist. Without that there is no morality in the world.” Golda Meier, 1967

“We do not fit the general pattern of humanity…” David Ben-Gurion

“…only God could have created a people so special as the Jewish people.” Gideon Levy

Zionism

“There are upwards of seven million Jews known to be in existence throughout the world… possessing more wealth, activity, influence and talents, than any body of people their number on earth….they will march in triumphant numbers, and possess themselves once more of Syria, and take their rank among the governments of the earth.” Mordecai Noah, 1818

“The ultimate goal … is, in time, to take over the Land of Israel and to restore to the Jews the political independence they have been deprived of for these two thousand years…. The Jews will yet arise and, arms in hand (if need be), declare that they are the masters of their ancient homeland.” Vladimir Dubnow, 1882

“…the spirit of the age is approaching ever closer to the essential Jewish emphasis on real life.” Moses Hess, 1862

“…Jews are a nation which, having once acted as the leaven of the social world, is destined to be resurrected with the rest of the civilized nations.” Moses Hess, 1862

“Today we may be moribund, but tomorrow we shall surely awaken to life; today we may be in a strange land, but tomorrow we will dwell in the land of our fathers; today we may be speaking alien tongues, but tomorrow we shall speak Hebrew.” Eliezer Ben-Yehudah, 1880

“…we must seek a home with all our hearts, our spirit, our soul.” Peretz Smolenskin, 1881

“Let sovereignty be granted us over a portion of the globe large enough to satisfy the rightful requirements of a nation: the rest we shall manage for ourselves.” Theodore Herzl, 1896

“Palestine is first and foremost not a refuge for East European Jews, but the incarnation of a reawakening sense of national solidarity.” Albert Einstein, 1921

Zionism:Weaponizing Antisemitism

“The anti-Semites will become our most dependable friends, the anti-Semitic countries our allies.” Theodore Herzl, 1896

“The struggle of Jews for unity and independence…is calculated to attract the sympathy of people to whom we are rightly or wrongly obnoxious.” Leo Pinsker

“The Western form of anti-Semitism—the cosmic, satanic version of Jew hatred—provided solace to wounded [Arab] feelings.” Bernard Lewis, 2006

Zionism: Ethnic Cleansing

“Will those [Palestinians] evicted really hold their peace and calmly accept what was done to them? Will they not in the end rise up to take back what was taken from them by the power of gold…And who knows, if they will not then be both prosecutors and judges…” Yitzhak Epstein, 1907

Zionism: Ambition

“Discussed with Bodenheimer the demands we will make. Area: from the Brook of Egypt to the Euphrates. Stipulate a transitional period with our own institutions. A Jewish governor for this period. Afterwards, a relationship like that between Egypt and the Sultan.” Theodore Herzl, 1898

“We should prepare to go over to the offensive. Our aim is to smash Lebanon, Trans-Jordan, and Syria. The weak point is Lebanon, for the Moslem regime is artificial and easy for us to undermine. We shall establish a Christian state there, and then we will smash the Arab Legion, eliminate Trans-Jordan; Syria will fall to us. We then bomb and move on and take Port Said, Alexandria and Sinai.” David Ben-Gurion May 1948

Zionism: Destabilizing Logic

“Will those [Palestinians] evicted really hold their peace and calmly accept what was done to them? Will they not in the end rise up to take back what was taken from them by the power of gold…And who knows, if they will not then be both prosecutors and judges…” Yitzhak Epstein, 1907

“God forbid that we should harm any people, much less a great people whose hatred is most dangerous to us.” Yitzhak Epstein, 1907

“As to the war against the Jews in Palestine….it was evident twenty years ago that the day would come when the Arabs would stand up against us.”Ahad Ha’am, 1911

“Two important phenomena, of the same nature, but opposed, are emerging at this moment in Asiatic Turkey. They are the awakening of the Arab nation and the latent effort of the Jews to reconstitute on a very large scale the ancient kingdom of Israel. These movements are destined to fight each other continually until one of them wins.” Najib Azouri, 1905

“It is all bad and I told Balfour so. They are making [the Middle East] a breeding place for future war.” Col. Edward Mandell House, 1917

“The question is, do we want to conquer Palestine now as Joshua did in his day – with fire and sword?” Judah L. Magnes, 1929

“It is our destiny to be in a state of continued war with the Arabs.” Arthur Rupin, 1936

“The day we lick the Arabs, that is the day, I think, when we shall be sowing the seeds of an eternal hatred of such dimensions that Jews will not be able to live in that part of the world for centuries to come.” Judah L. Magnes, 1947

“The state of Israel has had explosives – the grievances of hundreds of thousands of displaced Arabs – built into its very foundations.” Isaac Deutscher, 1954

“Why should the Arabs make peace? If I were an Arab leader I would never make terms with Israel. That is natural: we have taken their country.” David Ben-Gurion, 1956

“Historical logic points to the eventual dissolution of the Jewish state. The powers around us are so great. There is such a strong will to annihilate us that the odds look very poor.” Benny Morris, 2008

Zionism: Demographic Threat

“In Jewish cities, villages and kibbutzim … families are having 1.2 children. For theYishuv, that spells extinction.” David Ben-Gurion, March 1943

 Christian Zionism

“…we welcome the friendship of Christian Zionists.” Theodore Herzl, 1897

“The entire Christian church, in its variety of branches… will be compelled… to teach the history and development of the nascent Jewish state. No commonwealth on earth will start with such propaganda for its exploitation in world thought, or with such eager and minute scrutiny, by millions of people, of its slightest detail.” A. A. Berle, 1918

“Christian Zionists favor Jewish Zionism as a step leading not to the perpetuation but to the disappearance of the Jews.” Morris Jastrow, 1919

“…Zionism has but brought to light and given practical form and a recognized position to a principle which had long consciously or unconsciously guided English opinion.” Nahum Sokolow, 1919

“Christian Zionism and Jewish Zionism have combined to create an international alliance superseding anything that NATO or UN has to offer.” Daniel Lazare, 2003

“Put positively: Other than Israel’s Defense Forces, American [Christian] Zionists may be the Jewish state’s ultimate strategic asset.” Daniel Pipes, July 2003

Destabilizing Logic: Alienating Muslims

“…it seems to me and all members of my office acquainted with the Middle East that the policy which we are following [support for partition]…is contrary to the interests of the United States and will eventually involve us in international difficulties….we are forfeiting the friendship of the Arab world…[and] incurring long-term Arab hostility towards us.” Loy Henderson, November 1947

“US prestige in the Muslim world has suffered a severe blow, and US strategic interests in the Mediterranean and Near East have been seriously prejudiced.” George F. Kennan, January 1948

“You can trace the resurgence of what we call Islamic extremism to the Six Day War.” Michael Oren, 2007

Destabilizing Logic: Rise Of Israel/Six-Day War of June 1967

“Israel was now [after 1967] seen by the West, and primarily Washington, as a regional superpower and a desirable ally among a bevy of fickle, weak Arab states.” Benny Morris, 2001

“The glory of past ages no longer is to be seen at a distance but is, from now on, part of the new state…” Editorial in Haaretz, June 8, 1967

“We have returned to our holiest places, we have returned in order not to part from them ever again.” Moshe Dayan, June 9, 1967

“A messianic, expansionist wind swept over the country. Religious folk spoke of a “miracle” and of “salvation”; the ancient lands of Israel had been restored to God’s people.” Benny Morris, 2001

Zionism: Support of Western Imperialist Powers

“If His Majesty the Sultan were to give us Palestine…[w]e should there form a portion of a rampart of Europe against Asia, an outpost of civilization as opposed to barbarism.” Theodore Herzl, 1896

“Don’t worry, Dr. Wise, Palestine is yours.” Woodrow Wilson, March 1919

“The United States has a special relationship with Israel in the Middle East comparable only to that which it has with Britain over a wide range of world affairs…I think it is quite clear that in case of an invasion the United States would come to the support of Israel.” John F. Kennedy, December 1962

Zionism: Incremental Strategy

“Erect a Jewish state at once, even if it is not on the whole land. The rest will come in the course of time. It must come.” David Ben-Gurion, 1937

“Egypt is the only state among the Arab countries that constitutes a real state and is forging a people inside it. It is a big state. If we could arrive at the conclusion of peace with it, it would be a tremendous conquest for us.” David Ben-Gurion, 1949

Settler-Colonialism/Ethnic Cleansing

“As soon as we have a big settlement here we’ll seize the land, we’ll become strong, and then we’ll take care of the Left Bank [of the Jordan River]. We’ll expel them from there, too. Let them go back to the Arab countries.” A Jewish settler, 1891

“[We] must be prepared either to drive out by the sword the [Arab] tribes in possession as our forefathers did or grapple with the problem of a large alien population, mostly Mohammedan and accustomed for centuries to hate us.” Israel Zangwill, 1905

“… Palestine shall be as Jewish as England is English, or America is American.” Chaim Weizmann, 1919

“I support compulsory transfer. I do not see in it anything immoral.” David Ben-Gurion, 1938

“We are a generation of settlers, and without the steel helmet and the gun barrel, we shall not be able to plant a tree or build a house.” Moshe Dayan, April 1956

“Zionism comprises a belief that Jews are a nation, and as such are entitled to self-determination as all other nations are.” Emanuele Ottolenghi, 2003

“Without the uprooting of the Palestinians, a Jewish state would not have arisen here.” Benny Morris, 2004

Jewish Power

“There are upwards of seven million Jews known to be in existence throughout the world… possessing more wealth, activity, influence and talents, than any body of people their number on earth….they will march in triumphant numbers, and possess themselves once more of Syria, and take their rank among the governments of the earth.” Mordecai Noah, 1818

“When we sink, we become a revolutionary proletariat…when we rise, there rises also our terrible power of the purse.” Theodore Herzl, 1896

““If His Majesty the Sultan were to give us Palestine, we could in return undertake to regulate the whole finances of Turkey.” Theodore Herzl, 1896

“…Jews are a great power in journalism throughout the world.” Israel Zangwill, 1914

“In large parts of Eastern Europe [during the early decades of the twentieth century], virtually the whole “middle class” was Jewish.” Yuri Slezkin, 2004

“The expansion and consolidation of United States Jewry in the late nineteenth and twentieth centuries was as important in Jewish history as the creation of Israel itself; in some ways more important. For, if the fulfillment of Zionism gave the harassed diaspora an ever-open refuge with sovereign rights to determine and defend its destiny, the growth of US Jewry was an accession of power of an altogether different order, which gave Jews an important, legitimate and permanent part in shaping the policies of the greatest state on earth.” Paul Johnson

“…the Jews from every tribe have descended in force, and they are determined to break in with a jimmy if they are not let in.” Edward House, October 1917

 Jewish Power: Jewish Lobby

“I’m sorry, gentlemen, but I have to answer to hundreds of thousands who are anxious for the success of Zionism: I do not have hundreds of thousands of Arabs among my constituents.” President Harry Truman, November 1945

“I know I was elected because of the votes of American Jews. I owe them my election. Tell me, is there something I can do for the Jewish people?” President John F. Kennedy, December 1961

“Without this lobby Israel would have gone down the drain.” Isaiah (Si) Kenen

“During every congressional campaign, each candidate for every seat is asked to describe his or her views on the Middle East. Most office-seekers happily comply in writing. AIPAC then shares the results with its members, helping them to decide who is the most pro-Israel.” J. J. Goldberg, 1996

“AIPAC has one enormous advantage. It really doesn’t have any opposition.” Douglas Bloomfield, 2003

“In the last two decades between 1980 and 2000, American Jews gained power and influence beyond anything that they had ever experienced.” Stephen Schwartz, 2006

“A lobby is like a night flower: it thrives in the dark and dies in the sun.” Steven Rosen, 2005

“If Israel nuked Chicago, Congress would approve.” Steve Reed, 2009

“1000 Jewish lobbyists are on Capitol Hill against little old me.” President George H. Bush, September 1991

“… before I was elected to office I vowed to be an unshakable supporter of Israel. I have kept that commitment.” President Bill Clinton May 1995

“…I will bring to the White House an unshakable commitment to Israel’s security.” Barack Obama, June 2008

Zionism versus Saving Jewish Lives

“If I knew that it was possible to save all the [Jewish] children in Germany by transporting them to England, but only half by transporting them to Palestine, I would choose the second.” David Ben-Gurion, 1938

“If I am asked could you give money from UJA [United Jewish Appeal] moneys to rescue Jews? I say ‘No; and I say again, No.” Itzhak Greenbaum, 1943RedditEmail

M. Shahid Alam is Emeritus Professor, Department of Economics, Northeastern University. He is the author of Israeli Exceptionalism (Springer, 2008) and Yardstick of Life (KDP, 2024), a book of poetry. Read other articles by M. Shahid.

Tuesday, November 19, 2024

SPACE / COSMOS

Egg-shaped galaxies may be aligned to the black holes at their hearts, astronomers find


The Conversation
November 18, 2024

The active galaxy Centaurus A, with jets emanating from the central black hole. ESO/WFI (Optical); MPIfR/ESO/APEX/A.Weiss et al. (Submillimetre); NASA/CXC/CfA/R.Kraft et al. (X-ray), CC BY

Black holes don’t have many identifying features. They come in one color (black) and one shape (spherical).

The main difference between black holes is mass: some weigh about as much as a star like our Sun, while others weigh around a million times more. Stellar-mass black holes can be found anywhere in a galaxy, but the really big ones (known as supermassive black holes) are found in the cores of galaxies.

These supermassive behemoths are still quite tiny when seen in cosmic perspective, typically containing only around 1% of their host galaxy’s mass and extending only to a millionth of its width

However, as we have just discovered, there is a surprising link between what goes on near the black hole and the shape of the entire galaxy that surrounds it. Our results are published in Nature Astronomy.

When black holes light up

Supermassive black holes are fairly rare. Our Milky Way galaxy has one at its centre (named Sagittarius A*), and many other galaxies also seem to host a single supermassive black hole at their core.


Under the right circumstances, dust and gas falling into these galactic cores can form a disk of hot material around the black hole. This “accretion disk” in turn generates a super-heated jet of charged particles that are ejected from the black hole at mind-boggling velocities, close to the speed of light.

When a supermassive black hole lights up like this, we call it a quasar.

How to watch a quasar

To get a good look at quasar jets, astronomers often use radio telescopes. In fact, we sometimes combine observations from multiple radio telescopes located in different parts of the world.

Using a technique called very long baseline interferometry, we can in effect make a single telescope the size of the entire Earth. This massive eye is much better at resolving fine detail than any individual telescope.

As a result, we can not only see objects and structures much smaller than we can with the naked eye, we can do better than the James Webb Space Telescope.



Black holes are millions of times smaller than galaxies, yet make jets that are pointed in the same direction as the entire galaxy. Optical image: NASA, ESA, R.M. Crockett (University of Oxford, U.K.), S. Kaviraj (Imperial College London and University of Oxford, U.K.), J. Silk (University of Oxford), M. Mutchler (Space Telescope Science Institute, Baltimore, USA), R. O'Connell (University of Virginia, Charlottesville, USA), and the WFC3 Scientific Oversight Committee. Top right: MOJAVE Collaboration, NRAO/NSF. Bottom right: Event Horizon Telescope / ESO (same as before) CC BY-SA

This is the technique that was used to make the first “black hole image” in 2019, showing the halo of light generated around the supermassive black hole hosted by the galaxy M87.


Quasar jets that can be detected using very long baseline interferometry can be millions of light years long and are almost always found in elliptical galaxies. Using very long baseline interferometry, we can observe them all the way down to a few light years or so from their black hole of origin.

The direction of the jet near its source tells us about the orientation of the accretion disk, and so potentially the properties of the black hole itself.


Connection to the host galaxy


What about the host galaxies? A galaxy is a three-dimensional object, formed of hundreds of billions of stars.

But it appears to us (observed in optical or infrared) in projection, either as an ellipse or a spiral. We can measure the shape of these galaxies, tracing the profile of starlight, and measure the long axis and short axis of the two-dimensional shape.

In our paper, we compared the direction of quasar jets with the direction of this shorter axis of the galaxy ellipse, and found that they tend to be pointing in the same direction. This alignment is more statistically significant than you would expect if they were both randomly oriented.

This is surprising, as the black hole is so small (the jets we measure are only a few light years in length) compared to the host galaxy (which can be hundreds of thousands or even millions of light years across).

It is surprising that such a relatively small object can affect, or be affected by, the environment on such large scales. We might expect to see a correlation between the jet and the local environment, but not with the whole galaxy.
How galaxies form

Does this have something to say about the way galaxies form?


Spiral galaxies are perhaps the most famous kind of galaxy, but sometimes they collide with other spirals and form elliptical galaxies. We see these three-dimensional egg-shaped blobs as two-dimensional ellipses on the sky.

The merger process triggers quasar activity in ways we don’t fully understand. As a result, almost all quasar jets that can be detected using very long baseline interferometry are hosted in elliptical galaxies.

The exact interpretation of our results remains mysterious, but is important in the context of the recent James Webb Space Telescope discovery of highly massive quasars (with massive black holes), which have formed much earlier in the universe than expected. Clearly, our understanding of how galaxies form and how black holes influence that needs to be updated.


David Parkinson, Research Scientist in Astrophysics, The University of Queensland and Jeffrey Hodgson, Assistant Professor in Astrophysics, Sejong University

This article is republished from The Conversation under a Creative Commons license. Read the original article.


AnalySwift receives NASA STTR contract to transform spacecraft infrastructure for secondary uses during long-duration missions



Company and Purdue will develop composite heater layer and better engineering tools for composites



Purdue University

Kawai Kwok, Purdue University and AnalySwift, NASA STTR contract, reassembly 

image: 

Kawai Kwok, an associate professor in Purdue University’s School of Aeronautics and Astronautics, will be the primary investigator on a project with commercial software provider AnalySwift LLC. NASA has awarded AnalySwift a $156,424 Phase I Small Business Technology Transfer contract for the research.

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Credit: (Purdue University photo/Alan Cesar)




WEST LAFAYETTE, Ind. — AnalySwift LLC, a Purdue University-affiliated company, has received a Phase I STTR (Small Business Technology Transfer) contract from NASA worth $156,424.

Allan Wood, AnalySwift president and CEO, said the contract will fund two advancements: processes and hardware to disassemble spacecraft components and reassemble them for a secondary use, and software for multiphysics simulation and analysis of the involved thermoplastics.

Kawai Kwok, associate professor in Purdue’s School of Aeronautics and Astronautics, is the principal investigator.

Wood said long-duration crewed missions to the moon, Mars and beyond require infrastructure, such as trusses, to be constructed sustainably on these surfaces. But there are immense logistical challenges in transporting heavy and large payloads to space.

“The AnalySwift project proposes a novel method of disassembling and reassembling thermoplastic composite joints in space,” he said. “Our proposed method enables reconfiguration of truss structures in space, transitioning away from the current one-time use model to a scalable and sustainable approach.”

Kwok said spacecraft components could be quickly and easily repurposed into vastly different geometries.

“For example, a lunar lander support truss could become a vertical solar array support truss,” he said. “There are other applications, depending on mission needs using the same set of structural elements and innovative multiphysics modeling.”

Contract deliverables

Kwok said AnalySwift will develop a composite heater layer for the trusses and other infrastructure; it will be embedded with nanostructured carbon fillers. The layer will be made from the same thermoplastic matrix as the adhered composite parts. The layer will bring the matrix to the processing temperature for interface debonding by mechanical forces.

“Lightweight conductive nanocarbon thin films will be encapsulated inside semicrystalline thermoplastics such as PEEK (polyether ether ketone),” he said. “The disassembled struts and joints will be reassembled to the repurposed configuration via resistance welding using the same or additional heaters. The proposed in situ heating and reassembly method enables spacecraft components to be reutilized, which greatly reduces the logistical footprint to deliver technologies to space.”

Liang Zhang, senior research scientist at AnalySwift, said the company also will develop better engineering tools for composites, enabling reliable multiphysics simulation of their technique to repurpose lightweight structures made from thermoplastics.

“Theoretical and computational developments will include a new software tool or module, Thermoplastic Composites Multiphysics,” he said. “This multiphysics modeling framework will simulate the debonding and bonding processes of thermoplastic composite joint-strut interfaces using embedded carbon nanoheaters.”

Kwok said the framework has broader applications for thermoplastics.

“Advancements include developing multiphysics models and data for electrical heating and welding, including establishing relations between bonding strength and the process conditions of temperature, pressure and time,” he said. “More specifically, the disassembly and assembly processes of a nanocomposite is simulated using a third-party commercial finite element code with user subroutines defining the governing behavior of the material system.”

Zhang said AnalySwift’s multiphysics simulation tool will determine force, pressure and temperature histories during assembly and disassembly processes.

“More specifically, it will incrementally solve the constitutive relations as an initial value problem, extract temperature distributions at specific time points, and calculate the time and power required for completion,” he said.

Non-space applications

Wood said the processes and hardware advancements for disassembly and reassembly are more applicable to space applications, but the software has other potential uses.

“It can be particularly useful where simulation tools can improve utilization possibilities for high-performance thermoplastics,” he said. “Additional applications can be likely for aerospace, defense, automotive, marine, energy, electronics, sporting goods and medical devices. Applications also extend beyond simulation and into repair for thermoplastics.”

About AnalySwift

AnalySwift LLC is a provider of composite simulation software, which enables an unprecedented combination of efficiency and accuracy, including multiphysics structural and micromechanics modeling. Drawing on cutting-edge university technology, AnalySwift’s powerful solutions save orders of magnitude in computing time without a loss of accuracy so users can consider more design options and arrive at the best solution more quickly. The technologies deliver the accuracy of detailed 3D finite element analysis at the efficiency of simple engineering models. SwiftComp was developed at Purdue University and licensed from the Purdue Research Foundation. Contact AnalySwift at info@analyswift.com.

About Purdue Innovates Office of Technology Commercialization

The Purdue Innovates Office of Technology Commercialization operates one of the most comprehensive technology transfer programs among leading research universities in the U.S. Services provided by this office support the economic development initiatives of Purdue University and benefit the university’s academic activities through commercializing, licensing and protecting Purdue intellectual property. In fiscal year 2024, the office reported 145 deals finalized with 224 technologies signed, 466 invention disclosures received, and 290 U.S. and international patents received. The office is managed by the Purdue Research Foundation, a private, nonprofit foundation created to advance the mission of Purdue University. Contact otcip@prf.org for more information.

About Purdue University

Purdue University is a public research institution demonstrating excellence at scale. Ranked among top 10 public universities and with two colleges in the top four in the United States, Purdue discovers and disseminates knowledge with a quality and at a scale second to none. More than 105,000 students study at Purdue across modalities and locations, including nearly 50,000 in person on the West Lafayette campus. Committed to affordability and accessibility, Purdue’s main campus has frozen tuition 13 years in a row. See how Purdue never stops in the persistent pursuit of the next giant leap — including its first comprehensive urban campus in Indianapolis, the Mitch Daniels School of Business, Purdue Computes and the One Health initiative — at https://www.purdue.edu/president/strategic-initiatives.

Media contact: Steve Martin, sgmartin@prf.org


New idea may crack enigma of the Crab Nebula’s ‘zebra’ pattern



University of Kansas
Zebra-pattern pulsar 

image: 

Medvedev modeled wave diffraction off a circular reflecting region with radially varying index of refraction outside of it to better understand the Crab Nebula’s zebra pattern.

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Credit: Mikhail Medvedev




LAWRENCE — A theoretical astrophysicist from the University of Kansas may have solved a nearly two-decade-old mystery over the origins of an unusual "zebra" pattern seen in high-frequency radio pulses from the Crab Nebula.

His findings have just been published in Physical Review Letters (PRL), among the most prestigious physics journals.

The Crab Nebula features a neutron star at its center that has formed into a 12-mile-wide pulsar pinwheeling electromagnetic radiation across the cosmos.

“The emission, which resembles a lighthouse beam, repeatedly sweeps past Earth as the star rotates,” said lead author Mikhail Medvedev, professor of physics & astronomy at KU. “We observe this as a pulsed emission, usually with one or two pulses per rotation. The specific pulsar I’m discussing is known as the Crab Pulsar, located in the center of the Crab Nebula 6,000 light years away from us.”

The Crab Nebula is the remnant of a supernova that appeared in 1054.

“Historical records, including Chinese accounts, describe an unusually bright star appearing in the sky,” said the KU researcher.

But unlike any other known pulsar, Medvedev said the Crab Pulsar features a zebra pattern — unusual band spacing in the electromagnetic spectrum proportional to band frequencies, and other weird features like high polarization and stability.

“It’s very bright, across practically all wave bands,” he said. “This is the only object we know of that produces the zebra pattern, and it only appears in a single emission component from the Crab Pulsar. The main pulse is a broadband pulse, typical of most pulsars, with other broadband components common to neutron stars. However, the high-frequency interpulse is unique, ranging between 5 and 30 gigahertz — frequencies similar to those in a microwave oven.”

Since this pattern was discovered in a 2007 paper, the KU researcher said the pattern had proved “baffling” for investigators.

“Researchers proposed various emission mechanisms, but none have convincingly explained the observed patterns,” he said.

Using data from the Crab Pulsar, Medvedev established a method using wave optics to gauge the density of the pulsar’s plasma – the “gas” of charged particles (electrons and positrons) — using a fringe pattern found in the electromagnetic pulses.

“If you have a screen and an electromagnetic wave passes by, the wave doesn’t propagate straight through,” Medvedev said. “In geometrical optics, shadows cast by obstacles would extend indefinitely — if you’re in the shadow, there’s no light; outside of it, you see light. But wave optics introduces a different behavior — waves bend around obstacles and interfere with each other, creating a sequence of bright and dim fringes due to constructive and destructive interference.”

This well-known fringe pattern phenomenon is caused by consistent constructive interference but has different characteristics when radio waves propagate around a neutron star.

“A typical diffraction pattern would produce evenly spaced fringes if we just had a neutron star as a shield,” the KU researcher said. “But here, the neutron star’s magnetic field generates charged particles constituting a dense plasma, which varies with distance from the star. As a radio wave propagates through the plasma, it passes through dilute areas but is reflected by dense plasma. This reflection varies by frequency: Low frequencies reflect at large radii, casting a bigger shadow, while high frequencies create smaller shadows, resulting in different fringe spacing.”

In this way, Medvedev determined the Crab Pulsar’s plasma matter causes diffraction in the electromagnetic pulses responsible for the neutron star’s singular zebra pattern.

“This model is the first one capable of measuring those parameters,” Medvedev said. “By analyzing the fringes, we can deduce the density and distribution of plasma in the magnetosphere. It's incredible because these observations allow us to convert fringe measurements into a density distribution of the plasma, essentially creating an image or performing tomography of the neutron star's magnetosphere.”

Next, Medvedev said his theory can be tested with collection of more data from the Crab Pulsar and fine-tuned by factoring in its powerful and strange gravitational and polarization effects. The new understanding of how a plasma matter alters a pulsar’s signal will change how astrophysicists understand other pulsars.

“The Crab Pulsar is somewhat unique — it’s relatively young by astronomical standards, only about a thousand years old, and highly energetic,” he said. “But it’s not alone; we know of hundreds of pulsars, with over a dozen that are also young. Known binary pulsars, which were used to test Einstein’s general relativity theory, can also be explored with the proposed method. This research can indeed broaden our understanding and observation techniques for pulsars, particularly young, energetic ones.”