UCD RESEARCH PROVES THEORY ON STAR GROWTH

Dr Rebeca García López, an Ad Astra Fellow of the UCD School of Physics, and her team have recently proven a 30-year-old theory of how stars use their magnetic field lines to regulate their size and growth. Jade Norton reports.

From birth to death, a star is a massive body made of a variety of gases, but the binding force that allows the star to grow whilst also keeping it from disintegrating out into space has been under consideration for many years. It is not easy for a massive, gravitating body to collect dust and gas, nor is it easy to keep, as the star must find a way around the concept of conservation of angular momentum. This means that for the star to grow the gases surrounding it must keep an orbital distance rather than falling onto its surface. To maintain the stereotypical spherical shape commonly attributed to stars, these gases interact with the star’s magnetic field which is similar to that of Earth’s. It is usual for stars to have magnetic fields and it is possible to see the magnetic field of our closest star - the Sun - from the Northern or Southern lights, which visualise the particles that have been ejected from the Sun and are directed to the poles that protect the Earth. Research undertaken by Dr Rebeca García López and her team aimed to understand a theory postulated 30 years ago and, due to improving technology, they were able to discern the exact physical concept that is used to the binding force holding stars together.

The research, published in the science journal Nature, was led by Dr Rebeca García López, an Ad Astra Fellow in the UCD School of Physics, in collaboration with the Dublin Institute for Advanced Studies (DIAS), and the Max Planck Institute for Astronomy, Germany. They used observations from the GRAVITY telescope, based at the European Southern Observatory in the Andes Mountains of Chile, to measure the near-infrared radiation that was being emitted from the TW Hydrae, a young T Tauri star found in the constellation of Hydra. The GRAVITY telescope links the four 8-meter- telescopes of the VLT and uses a technique called interferometry to visualise stellar details that are so small they can not be seen by a single telescope.

From their observations they were able to conclude that the process the star was going through was called magnetospheric accretion. This is a process that uses the magnetic fields of the stars to guide gases that are falling centrally toward the star from the inner circumstellar disk to the surface. This means that stars gather material from around them using a disk-shaped magnetic field and it allows them to grow in mass. The magnetic fields guide the gases for the inner layer of the star to a surrounding disk in column-like flows, which essentially created a funnel guiding the particles that are similar to that of the poles of the Earth. GRAVITY was able to visualise the inner part of the gas disk surrounding TW Hydrae which showed that the light emitted from the star was located within three and a half times the radius of the star. This is significant as the small distance of the circumstellar disk is in conflict with the standard physical models and leads to the only plausible explanation of a physical model to be a magnetospheric accretion model.

The original theory was conceived by Max Camenzind, a German astrophysicist. He postulated an answer as to how matter manages to reach the accretion disk and overcome the conservation of angular momentum. His theory was magnetospheric accretion, but he was not able to prove it due to limitations in technology. It was from his work and others that Dr García López developed on and used the improvements in technology to understand where the extra energy created by the rotational momentum went to. This energy should have thrown all the gathered material back into space in a cycle of accumulation and simultaneous disintegration. However, observations from GRAVITY show a hydrogen emission across the radius which could be attributed to a stellar magnetosphere but due to their small size it makes them difficult to resolve and make an interpretation of the observation. This led to the idea that the hydrogen emission was due to accretion columns which are funnel flows of matter being added to the star. This is to be expected from magnetospheric accretion models rather than from wind emitted at a much larger distance.

Improvements in technology have allowed for many physical models to be proven that were discovered many years ago. Future observations will allow researchers to get a more detailed reconstruction of the processes that are being undertaken close to the star. A further avenue of research may be to find if the star’s axis of rotation is similar to or in the same location as the magnetic north and south poles, but due to the complex and diverse nature of magnetic fields this answer could also be 30 years in the future. No matter what the case is though, this research will only further drive progression in the field of astronomy and space science.

WHAT’S IN A NAME? WOULD A CIVIL OFFENCE BY ANY OTHER NAME BE AS CONTENTIOUS?

NESSA DENIHAN

Nessa Denihan dissects the government’s latest approach to mass gatherings.

Confusion and criticism enveloped the Government’s recent announcement that it would be made a civil offence to hold gatherings of over six people from three different households in a private home. It is understood that the Cabinet believed that criminalising such gatherings would be too extreme. Criminal actions are taken by the State against a defendant who will either be convicted or acquitted. Incarceration is the most severe penalty associated with the criminal process. In contrast, civil actions are between private parties. Parties found liable typically face monetary penalties.

The nebulous message communicated by the Tánaiste Leo Varadkar was one source of confusion. Varadkar stated that the civil action would be taken by the Minister for Health against individuals charged with this offence, rather than An Garda Síochána. Varadkar’s description of the act of holding such a gathering as a ‘civil offence’ provoked widespread confusion as it is a term seldom seen on the statute books in Ireland. Many leading Irish academics expressed their bewilderment with this term on social media. Dr Eoin O’Dell, Associate Professor of Law at Trinity College Dublin and Professor Fiona de Londras, Professor of Global Legal Studies at the University of Birmingham both tweeted to the effect that they were thus far unaware of the existence of civil offences under Irish law.

O’Dell suggested that Mr Varadkar misspoke and that the offence would be better described as ‘minor’. He surmised that the prohibited action in question would amount to a civil wrong, a “specific statutory example of social host liability in the tort of negligence”. O’Dell wryly noted that Mr Varadkar’s brief stint as a law student before he switched to medicine had not been of service to him on this occasion.

Civil offences would therefore appear to be an unexplored category of offence. It seems that an immediate fine would be the only applicable penalty. This possible misstatement could be seen as indicative of the unique Taoiseach-Tánaiste relationship between Mícheál Martin and Leo Varadkar. Since he has previously held the office of Taoiseach, a position he will return to in December 2022 if the current government remains in power, Varadkar is not quite second fiddle to Martin. Political correspondent with The Irish Times Harry McGee has compared their dynamic to the coleadership between the First Minister and the Deputy First Minister in Northern Ireland.

McGee claimed that we are witnessing the return of ‘Straight-Talking Leo’, a persona which refers to Varadkar’s tendency to speak his mind - often at the expense of his parliamentary colleagues. This was seen when Varadkar tweeted on August 21 expressing his sympathy with citizens and businesses in Kildare before any official announcement by the Taoiseach regarding the extension of the Kildare lockdown. Varadkar’s desire to be first to get the soundbite may be symptomatic of his forthrightness, or it may reflect that he does not truly feel that he has passed on the mantle of leadership to Martin. Varadkar may consider it important to keep a high profile until he reassumes the office of Taoiseach. It is also no secret that he is far savvier than Martin when it comes to image management and public relations.

“Shakespeare once asked what’s in a name, and it may be the case that there was much ado about nothing in relation to the labelling of the aforementioned offence. However, in the wake of the infamous gathering of the Oireachtas Golf Society, the Government is struggling to maintain

There was also significant backlash due to the perception that the Government is opting to crack down on relatively small gatherings in private homes which are subject to constitutional protection instead of addressing the clusters of Covid-19 cases in crowded Direct Provision centres and meat factories with subpar working conditions. This strategy has been interpreted as a response to the alleged spreading of coronavirus at house parties. Some critics viewed this as a governmental attempt to scapegoat young people to deflect from political inertia in the context of more systemic issues such as the disregard for workers’ rightsespecially those in precarious employment - and the ineffective framework for seeking asylum in Ireland. Although there is a commitment in the Programme for Government to ending the current system of Direct Provision, it is likely that any reform will be incremental and will therefore not alleviate the current situation. Should a vaccine combattind Covid-19 become available by 2021, it is doubtful that residents in Direct Provision centres would be first in line to receive it. As a result, it seems inevitable that these centres will continue to be hotbeds for the virus.

On 9 September, Dr David Kenny, coordinator of the Trinity College Dublin Covid-19 Law and Human Rights Observatory, testified before the Special Committee on Covid-19 Response that the regulations in question provided no power of entry. Kenny stated that holding a restricted gathering was not subject to a penal provision, but noted that the term ‘civil offence’ is not typically used in Irish law. Kenny concluded that there was a need for greater oversight of this regulation due to the credible but not definite constitutional objection to it. He considered it necessary to tackle the ongoing problem of frequent clusters of cases in Direct Provision centres, suggesting that, inter alia, applications for asylum could be expedited.

Shakespeare once asked what’s in a name, and it may be the case that there was much ado about nothing in relation to the labelling of the aforementioned offence. However, in the wake of the infamous gathering of the Oireachtas Golf Society, the Government is struggling to maintain authority against accusations of incompetence and hypocrisy. The ‘Golfgate’ scandal provoked outrage, sent the Irish media into a frenzy and resulted in the resignation of the Minister for Agriculture and EU Commissioner Phil Hogan. The spectre of this incident lingers in the form of the former Chief Justice Susan Denham’s non-statutory review of the recent appointee to the Supreme Court Séamus Woulfe’s attendance at the dinner. While any governmental action is assumed to be taken in the interest of public health and based on expert advice, both Fianna Fáil and Fine Gael - who were heavily damaged by this scandal - risk alienating younger voters who proved themselves more likely to support the most powerful party in opposition, Sinn Féin, in February’s general election.

WHO DOES KAMALA HARRIS REALLY REPRESENT?

“She represents my story – my past and my future.” The words of Anita Thawani Bucio, a firstgeneration Indian-American working mother, are rife with respect and promise in the pages of the New York Times this August.

“I never thought I’d see the day when my next V.P. shared the same skin color, no-nonsense attitude, and even the same middle name.” declares Shakunthala Devi Shiwnath, a 29-year-old Bostonian. “Representation matters. Role models matter.” says Goerg’ann Cattelona, a grassroots organizer from Indiana.

And she’s right. Representation matters. Especially in a context where women, and Black and Brown women in particular, have faced serious underrepresentation throughout US political history. In addition, this demographic encounter serious oppression on the ground, with nearly a quarter of the group living below the official poverty line. The announcement that Kamala Harris would be the first African American and the first Asian American woman on a Democratic Party ticket was therefore a welcome one. Harris’ position as the prospective vice president under the Biden campaign indicates a huge leap for the future of American politics and the fate of marginalized communities. But in the context of the ongoing Black Lives Matter movement, Harris’ symbolic potential is only worthwhile if fulfilled. Whether it is likely to be fulfilled requires serious investigation into her track record and political ability, not just her heritage. When the stakes are so high for those most affected, we must ask; is Kamala Harris truly representative of their plight, and more importantly, is she committed to making the structural changes necessary in order to tackle it?

With an estimated wealth of six million dollars after her marriage to attorney Douglas Emhoff, critics have placed doubts on Harris’ ability to adequately understand the struggles of those who suffer the most; poor Black women. Keeanga-Yamahtta Taylor, for the New Yorker, argues that “class position is not an intangible extra that can be discarded when we talk about representation.” Indeed, Harris’ place of privilege could hinder her ability to empathise with those she is expected to vouch for most.

Intersectionality aside, there is no reason that her elite standing should prevent her from implementing progressive policies, particularly when she was raised by an activist immigrant mother, stood among the first students to attend desegregated Berkeley schools, and still faces discrimination from Republican opposition.

So, is she likely to administer said policies? Unfortunately, Harris’ race does not guarantee that she will champion a Black-centered agenda. And she certainly has not made any such promises so far. In fact, both she and Biden have done little to explain how their illustrative gestures towards change will morph into the material and systemic reform needed to support millions of underprivileged minority women. Because they have not given us a lot to go on, all that is left to do is examine their histories.

While Harris impressively condemned Biden’s racist past in a Democratic debate earlier this year, her recent solidarity is evidence of her tendency to bend to the will of superior powers when it suits her own agenda. Her inconsistent support of Bernie Sander’s ‘Medicare For All’ plan, and companionship with Sheryl Sandberg provides further proof. She befriended the Facebook CEO while serving as Attorney General, standing by as California’s tech industry expanded dangerously and affected the lives of the lowest socio-economic class; those she was placed in power to protect.

Contradictory character established, her actions as California’s lead prosecutor place her further from the core interests of Black and Brown communities. While in charge, she opposed measures to investigate shootings involving officers, appealed a judge’s effort to end the death penalty, and imposed policing policies that arrested truant parents, majorly impacting those who are “overwhelmingly poor, Black and Brown, and struggling”. In the current climate, women leading the Black Lives Matter movement are advocating for radical change in the country’s criminal legal system. Can they really depend on the “top cop” and her moderate, stateforce approach to enact the transformation that campaigners desire?

At the same time, it is injudicious to ignore the political constraints that the biracial candidate has faced throughout her professional life. The context of her rise highlights a time in which her opposition of a criminal execution in 2004 almost cost her career.

Barack Obama’s tough penalty legislation against offenders while state senator is further confirmation that during the early 2000s, being deemed procriminal was dangerous for Black politicians and their progression. As Peter Beinart notes, “Commentators can ignore the way American politics actually works. Black women who want a career in national politics cannot.” Harris’ cautionary tactics could be the only reason her name is appearing on the 2020 party ticket in the first place. And in a race against Donald Trump and conservative America, no matter how Harris arrived at where she is today, maybe it is more important that she stays there.

Perhaps Black and Brown female activists would feel more assured if Harris clearly offered such reassurance. Perhaps clarity remains out of reach until her seat in power is secured. But how much power does Harris need before she begins to use her position for good? And how much longer can the Black Lives Matter movement wait?

Representation matters. But we must not conflate symbolic firsts with the assumption that a biracial woman at the helm will make a meaningful difference in minority lives. That a Black captain equals a Black policymaking plan. For that to happen, Harris must not only be a descriptive representative, she must be a substantive one. She has the experience, debating credentials and potential to affect real change. Likely a presidential front runner for 2024, she could gain the capacity to listen to Black and Brown women, uniquely understand them, and implement the progressive reforms necessary to ensure their calls are answered. Whether or not she will? Time will tell. Meanwhile, the plight of those affected first-hand continues across US streets and worldwide, with Black Lives Matter demonstrations unexpected to cease any time soon.