UQ physics student works out ‘paradox-free’ time travel

A young University of Queensland student says he has found a way to “square the numbers” and prove that “paradox-free” time travel is theoretically possible in our universe.

From Back To The Future to Terminator to 12 Monkeys, stories dealing with time travel invariably have had to grapple with an age-old head-scratcher.

The so-called “grandfather paradox” – that a time traveller could kill their grandparent, preventing their own birth – broadly describes the logical inconsistency that arises from any action that would change the past.

But Germain Tobar, a fourth-year Bachelor of Advanced Science student, believes he has solved the riddle.

“Classical dynamics says if you know the state of a system at a particular time, this can tell us the entire history of the system,” he said in a statement.

“This has a wide range of applications, from allowing us to send rockets to other planets and modelling how fluids flow. For example, if I know the current position and velocity of an object falling under the force of gravity, I can calculate where it will be at any time.”

Einstein’s theory of general relativity, however, predicts the existence of time loops or time travel, “where an event can be both in the past and future of itself – theoretically turning the study of dynamics on its head”.

Mr Tobar said a unified theory that could reconcile both traditional dynamics and Einstein’s theory of relativity was the holy grail of physics. “But the current science says both theories cannot both be true,” he said.

“As physicists, we want to understand the universe’s most basic, underlying laws and for years I’ve puzzled on how the science of dynamics can square with Einstein’s predictions. I wondered, ‘Is time travel mathematically possible?’”

Mr Tobar and his supervisor, UQ physicist Dr Fabio Costa, say they have found a way to “square the numbers” – and that the findings have fascinating consequences for science. “The maths checks out – and the results are the stuff of science fiction,” Dr Costa said.

Dr Costa gives the example of travelling in time in an attempt to stop COVID-19’s “patient zero” being exposed to the virus.

As the grandfather paradox shows, if you stopped that individual getting infected, “that would eliminate the motivation for you to go back and stop the pandemic in the first place”.

“This is a paradox – an inconsistency that often leads people to think that time travel cannot occur in our universe,” he said.

“Some physicists say it is possible, but logically it’s hard to accept because that would affect our freedom to make any arbitrary action. It would mean you can time travel, but you cannot do anything that would cause a paradox to occur.”

But the researchers, whose findings appear in the journal Classical and Quantum Gravity, say their mathematical modelling shows that neither of these conditions have to be the case.

Instead, they show it is possible for events to adjust themselves to be logically consistent with any action that the time traveller makes.

“In the coronavirus patient zero example, you might try and stop patient zero from becoming infected, but in doing so you would catch the virus and become patient zero, or someone else would,” Mr Tobar said.

“No matter what you did, the salient events would just recalibrate around you. This would mean that – no matter your actions – the pandemic would occur, giving your younger self the motivation to go back and stop it.”

He added, “Try as you might to create a paradox, the events will always adjust themselves, to avoid any inconsistency. The range of mathematical processes we discovered show that time travel with free will is logically possible in our universe without any paradox.”

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Cardinal George Pell returns to Rome for first time since child sex abuse convictions quashed

A spokeswoman for the Archdiocese of Sydney confirmed Cardinal Pell will fly out of Sydney today, but the purpose and duration of the visit is not known.

Cardinal Pell was leading the Secretariat of State, set up to reform the Vatican’s finances, when he took a leave of absence in 2017 to face charges of child sexual abuse.

The 79-year-old was convicted of sexually abusing two choir boys in the 1990s and was sentenced to six years in prison.

He had served 13 months of his sentence when his conviction was overturned by the High Court in April. He has been living in Sydney since his release.

Christopher Lamb is the Rome correspondent for Catholic news publication The Tablet and said all eyes would be on Cardinal Pell as he arrived in Rome. “The Cardinal has a number of supporters in Rome and some very loyal followers,” Lamb said.

“There will be a number of them who will be delighted to see him return — they always were very sceptical of the charges that were brought against him.

“However there will be others who will be concerned about the optics of a return by Cardinal Pell to Rome and the Vatican … particularly if the cardinal has a meeting, an audience, with Pope Francis.”

Vatican correspondent Joshua McElwee, from US newspaper the National Catholic Reporter, said Cardinal Pell was no longer employed by the Vatican and the reason for his visit was not clear. “At the moment he has no official role here,” McElwee said.

“Very likely he’s coming to put his affairs in order. I imagine he still has personal items here, things to bring home, perhaps an apartment to clean up. “I don’t know what else he would be doing other than those kind of things.”

Cardinal Pell’s return to Rome comes just days after the resignation of Cardinal Angelo Becciu who has been implicated in allegations of financial misconduct at the Vatican.

Cardinal Becciu previously worked in the Vatican’s Secretariat of State where he reportedly clashed with Cardinal Pell over reform of the Vatican’s finances.

But McElwee said it was not clear whether Cardinal Pell’s visit was connected to Cardinal Becciu’s resignation on Saturday.

“It’s known that Cardinal Pell and Cardinal Becciu butted horns when Cardinal Pell was in Rome,” McElwee said. “Becciu apparently was involved in some kind of alleged financial misdeeds and Pell has said that he raised issues about those at the time.

“It could be that Cardinal Pell is taking a victory lap here in Rome, but I don’t think it’s going to be more than a short visit.”

Lamb said Cardinal Pell’s visit coincided with a period of uncertainty in Pope Francis’s pontificate, with many speculating Cardinal Pell could be seeking to influence the outcome of a future conclave to decide the next Pope.

“Cardinal Pell is not someone who is openly disloyal to Pope Francis and has worked for Pope Francis,” Lamb said.

“But it is no secret that he has a different vision of the Church to the Pope and I suppose some people will be looking to see whether the Cardinal is involved in any pre-conclave manoeuvres, given we are almost eight years into Pope Francis’s pontificate. “There is a battle going on and the Cardinal is certainly seen by those who don’t like Francis as someone who is an ally.”

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“One Nation” party gets academic freedom change in return for vote

A legal definition of academic freedom that some universities say will make it harder for them to discipline racist or sexist academics will be included in the Morrison government’s proposed university funding laws in exchange for One Nation’s support for the bill.

The measure is one of several commitments One Nation say they have extracted from the government, which will need three crossbench votes to get its reforms through the Senate as early as next week.

Senator Pauline Hanson said One Nation’s two Senate votes were also contingent upon the government reinstating a 10 per cent discount for students who pay their fees upfront, and reinstating a seven-year limit for full-time students to receive HECS-HELP before they have to pay full fees.

One Nation has fostered a close relationship with academic Peter Ridd, who was sacked by James Cook University in 2018 following his public criticism of colleagues’ research on the impact of global warming on the Great Barrier Reef.

“[Education] Minister [Dan] Tehan has shown a strong willingness to listen to the recommendations of [Senator] Malcolm Roberts and myself, and he’s proving to have the courage to take a tough stand with the inclusion of our amendments,” Senator Hanson said.

One Nation wants the definition of academic freedom inserted into the Higher Education Support Act 2003 to be in line with the wording recommended by former High Court Chief Justice Robert French in his government-commissioned review of free speech at Australian universities.

There has been an ongoing debate about free speech at universities, and the review was ordered following concerns among coalition MPs about the influence of left wing activists on campus after protesters targeted author Bettina Arndt at Sydney University.

In his 2019 report, Mr French proposed inserting a lengthy definition into the Act that included “the freedom of academic staff to teach, discuss, and research and to disseminate and publish the results of their research” and to “make lawful public comment on any issue in their personal capacities”.

Mr Tehan declined to comment on the specifics of his negotiations with One Nation, but said he would continue to work with the crossbench to secure passage of the legislation.

“The Job-Ready Graduates legislation will provide more university places for Australian students, make it cheaper to study in areas of expected job growth and provide more funding and support to regional students and universities,” Mr Tehan said.

The government was already examining whether it should proceed with legislating the French definition of academic freedom, and called for public submissions in January, but ultimately did not include the measure as part of its current reforms.

In its submission to the government, the Innovative Research Universities, a grouping of seven institutions including La Trobe University, Western Sydney University and James Cook University, opposed the move. It said legislating the freedom for academics to provide public commentary in a personal capacity had the “potential to create highly undesirable employment disputes.”

“As the wording stands, for example, it would seem that a university academic would be within her or his rights to publicly declare they hold a racial, sexuality or gender prejudice against one or more of the students they are teaching,” the submission said.

“If challenged about holding such a view, they would seem to be able to defend themselves by claiming to have spoken in a personal capacity, not an academic one.”

Senator Hanson said her motivation was to address concerns among university lecturers who were worried about “pressures they faced over ‘how’ and ‘what’ they could teach.

“My interest is in putting a stop to this Marxist, left-leaning approach to teaching in our universities and instead, protect educators who teach using methods based on science and facts rather than ideology,” Senator Hanson said.

In his review, Mr French, chancellor of the University of Western Australia, concluded that “claims of a freedom of speech crisis on Australian campuses are not substantiated”, but outlined a model code for protecting free speech and academic freedom, which all universities agreed to adopt by the end of 2020.

In September, Dr Ridd accompanied Senator Roberts on week-long tour along the Queensland coast, holding press conferences to question the scientific consensus on the poor health of Great Barrier Reef’s and threat posed by farmers. Dr Ridd said he was meeting with National Senator Matt Canavan and local LNP candidate Ron Harding to discuss the same issues on Tuesday.

Dr Ridd is now seeking leave to appeal his wrongful dismissal claim in the High Court, after his initial victory was overturned by the Federal Court in July. The university has maintained that he was not dismissed for his views, but for “serious misconduct” and breaches of the university’s code in how he expressed them.

The government’s bill proposes a major restructuring of university funding by hiking fees for some courses, including by 113 per cent for humanities, in order to pay for cuts to STEM, nursing and teaching courses.

The government says the reforms will fund an extra 100,000 university places for domestic students by 2030, but universities have complained that total funding per student will decrease by six per cent on average.

In addition to securing One Nation’s two votes, the government will need to secure the support of either Tasmania Senator Jacqui Lambie or Centre Alliance Senator Stirling Griff, who are yet to public reveal how they intend to vote.

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Queensland Government grants approval for state’s third-largest coal mine with 1,000 jobs promised

Construction will soon get underway on what will become Queensland’s third-largest coal mine, 40 kilometres south of Moranbah in the Bowen Basin.

Premier Annastacia Palaszczuk announced the State Government had signed off on a mining lease for the Olive Downs Coking Coal Project, run by Pembroke Resources.

The central Queensland mine will have a production life of 80 years and the Government says it will create 1,000 jobs.

The Government did not provide forecasts for how much it would collect in mining royalties, but the number is expected to be in the billions.

“Let me say very clearly that not only do I support the coal industry here, but I’ve also been over to the steel mill in Japan,” Ms Palaszczuk said.

“Nearly every single household utilises steel in some form or another, and steel is going to be part of our lives for many years to come.”

Pembroke said it would produce up to 15 million tonnes of metallurgical coal per year.

It will be exported to international markets in Japan and China.

Pembroke CEO Barry Tudor said the mining lease approvals were the final hurdle to beginning stage one of the project.

“We are extremely pleased to have been granted the mining leases, having consulted extensively with the local community over the past four years,” he said.

“In addition to our commitment to the environment, we have focused on creating local jobs and proactively engaged with all stakeholders.”

Mr Tudor said the company had established a relationship with the traditional owners of the land, the Barada Barna.

“We have an Indigenous Land Use Agreement and Cultural Heritage Management Plan in place,” Mr Tudor said.

Ms Palaszczuk said she expected construction would start within months. “There’s no legal action with Olive Downs — Olive Downs is good to go,” she said.

Opposition leader Deb Frecklington criticised Ms Palaszczuk for her record on advancing resources projects, but said she supported the mining lease for Olive Downs.

Once complete, Olive Downs will be around the same size as the proposed Adani project.

Ms Palaszczuk said her Government had approved $21 billion in resource projects in the current parliamentary term.

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Posted by John J. Ray (M.A.; Ph.D.). For a daily critique of Leftist activities, see DISSECTING LEFTISM. To keep up with attacks on free speech see Tongue Tied. Also, don’t forget your daily roundup of pro-environment but anti-Greenie news and commentary at GREENIE WATCH . Email me here